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Volume 69 (2020): Issue 4 (December 2020)

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Volume 69 (2020): Issue 2 (June 2020)

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Volume 68 (2019): Issue 3 (September 2019)

Volume 68 (2019): Issue 2 (June 2019)

Volume 68 (2019): Issue 1 (March 2019)

Volume 67 (2018): Issue 4 (December 2018)

Volume 67 (2018): Issue 3 (September 2018)

Volume 67 (2018): Issue 2 (June 2018)

Volume 67 (2018): Issue 1 (January 2018)

Volume 66 (2017): Issue 4 (December 2017)

Volume 66 (2017): Issue 3 (September 2017)

Volume 66 (2017): Issue 2 (June 2017)

Volume 66 (2017): Issue 1 (March 2017)

Volume 65 (2016): Issue 4 (December 2016)

Volume 65 (2016): Issue 3 (August 2016)

Volume 65 (2016): Issue 2 (June 2016)

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Journal Details
Format
Journal
eISSN
2544-4646
First Published
04 Mar 1952
Publication timeframe
4 times per year
Languages
English

Search

Volume 67 (2018): Issue 2 (June 2018)

Journal Details
Format
Journal
eISSN
2544-4646
First Published
04 Mar 1952
Publication timeframe
4 times per year
Languages
English

Search

15 Articles

mini-review

access type Open Access

Non-antibiotics, Efflux Pumps and Drug Resistance of Gram-negative Rods

Published Online: 30 Jun 2018
Page range: 129 - 135

Abstract

Abstract

Non-antibiotic medicinal products consist of drugs with diverse activity against bacteria. Many non-antibiotics demonstrate direct anti-bacterial activity against Gram-positive cocci. The activity observed against Gram-negative rods is much lower and non-antibiotics primarily from the following groups: non-steroidal anti-inflammatory drugs, cardiovascular and antidepressant medicinal products demonstrate this activity. It has been shown that the low activity of some non-antibiotics or the absence of activity against Gram-negative rods is related, among other things, to the extrusion of these compounds from bacterial cells by multi-drug resistance efflux pumps. Substrates for the resistance-nodulation-division efflux systems include the following non-antibiotics: salicylate, diclofenac, ibuprofen, mefenamic acid, naproxen, amitriptyline, alendronate sodium, nicergoline, and ticlopidine. In addition, interactions between non-antibiotics and multi-drug resistance efflux pumps have been observed. It has also been revealed that depending on the concentration, salicylate induces expression of multi-drug resistance efflux pumps in Escherichia coli, Salmonella enterica subsp. enterica serotype Typhimurium, and Burkholderia cenocepacia. However, salicylate does not affect the expression of the resistance-nodulation-division efflux systems in Stenotrophomonas maltophilia and Acinetobacter baumannii. Most importantly, there were no effects of medicinal products containing some non-antibiotic active substances, except salicylate, as substrates of multi-drug resistance efflux pumps, on the induction of Gram-negative rod resistance to quinolones.

Keywords

  • MDR efflux pumps
  • antibiotic resistance
  • non-antibiotics
access type Open Access

Bacteriological, Clinical and Virulence Aspects of Aeromonas-associated Diseases in Humans

Published Online: 30 Jun 2018
Page range: 137 - 150

Abstract

Abstract

Aeromonads have been isolated from varied environmental sources such as polluted and drinking water, as well as from tissues and body fluids of cold and warm-blooded animals. A phenotypically and genotypically heterogenous bacteria, aeromonads can be successfully identified by ribotyping and/or by analysing gyrB gene sequence, apart from classical biochemical characterization. Aeromonads are known to cause scepticemia in aquatic organisms, gastroenteritis and extraintestinal diseases such as scepticemia, skin, eye, wound and respiratory tract infections in humans. Several virulence and antibiotic resistance genes have been identified and isolated from this group, which if present in their mobile genetic elements, may be horizontally transferred to other naive environmental bacteria posing threat to the society. The extensive and indiscriminate use of antibiotics has given rise to many resistant varieties of bacteria. Multidrug resistance genes, such as NDM1, have been identified in this group of bacteria which is of serious health concern. Therefore, it is important to understand how antibiotic resistance develops and spreads in order to undertake preventive measures. It is also necessary to search and map putative virulence genes of Aeromonas for fighting the diseases caused by them. This review encompasses current knowledge of bacteriological, environmental, clinical and virulence aspects of the Aeromonas group and related diseases in humans and other animals of human concern.

Keywords

  • aeromonad
  • diarrhea
  • multi-drug
  • resistance
  • virulence
access type Open Access

Brucella – Virulence Factors, Pathogenesis and Treatment

Published Online: 30 Jun 2018
Page range: 151 - 161

Abstract

Abstract

Brucellae are Gram-negative, small rods infecting mammals and capable of causing disease called brucellosis. The infection results in abortion and sterility in domestic animals (sheeps, pigs, rams etc). Especially dangerous for humans are: Brucella melitensis, Brucella suis, Brucella abortus, and Brucella canis that trigger unspecific symptoms (flu-like manifestation). Brucella rods are introduced via host cells, by inhalation, skin abrasions, ingestion or mucosal membranes. The most important feature of Brucella is the ability to survive and multiply within both phagocytic and non-phagocytic cells. Brucella does not produce classical virulence factors: exotoxin, cytolisins, exoenzymes, plasmids, fimbria, and drug resistant forms. Major virulence factors are: lipopolysaccharide (LPS), T4SS secretion system and BvrR/BvrS system, which allow interaction with host cell surface, formation of an early, late BCV (Brucella Containing Vacuole) and interaction with endoplasmic reticulum (ER) when the bacteria multiply. The treatment of brucellosis is based on two-drug therapy, the most common combinations of antibiotics are: doxycycline with rifampicin or fluoroquinolones with rifampicin. Currently, also other methods are used to disrupt Brucella intracellular replication (tauroursodeoxycholic acid or ginseng saponin fraction A).

Keywords

  • endoplasmic reticulum
  • macrophage
  • replication
  • virulence factors

original-paper

access type Open Access

Isolation of Bacteriocin-producing Staphylococcus spp. Strains from Human Skin Wounds, Soft Tissue Infections and Bovine Mastitis

Published Online: 30 Jun 2018
Page range: 163 - 170

Abstract

Abstract

A collection of 206 Staphylococcus spp. isolates was investigated for their ability to produce compounds exhibiting antistaphylococcal activity. This group included Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus xylosus strains recovered from bovine mastitis (n = 158) and human skin wounds and soft tissues infections (n = 48). Production of substances with antimicrobial activity was observed in six strains. Five of them were recovered from bovine mastitis, and one was isolated from the infected human skin wound. Three of the six antimicrobials produced by the different strains showed substantial loss of antimicrobial activity upon treatment with proteolytic enzymes, which suggests their peptidic structure. Additional studies have shown that one of the putative bacteriocins was efficiently secreted to the liquid medium, facilitating its large-scale production and isolation. The peptide produced by the M2B strain exhibited promising activity; however, against narrow spectrum of Staphylococcus spp. clinical and animal isolates. Growth inhibition was observed only in the case of 13 (including nine S. aureus, three S. xylosus and one S. epidermidis strains) out of 206 strains tested. Important advantage of the produced agent was its high thermal stability. Fifteen minutes of incubation at 90°C did not affect its antimicrobial potential. The highest efficiency of production of the agent was demonstrated in TSB medium after 24 hours at 37°C. The researches revealed that ability to production of bacteriocin among staphylococci is not very common. Only one (S. xylosus strain assigned as M2B) out of 206 strains tested produced satisfactory amounts of antistaphylococcal bacteriocin. In spite of that, we would encourage other researchers for investigation of their collections of Staphylococcus spp. isolates towards selection strains producing antimicrobial agents.

Keywords

  • antimicrobial peptides
  • antistaphylococcal agents
access type Open Access

Genetic Analysis Method for Staphylococcus chromogenes Associated with Goat Mastitis

Published Online: 30 Jun 2018
Page range: 171 - 180

Abstract

Abstract

Mastitis in goats is mainly caused by coagulase-negative Staphylococcus (CNS). The identification methods for this group are based on evaluating the expression of phenotypic characteristics such as the ability to metabolize various substrates; however, this is disadvantageous as these methods are dependent on gene expression. In recent years, genotyping methods such as the Multiple Locus Variable-Number Tandem Repeat Analysis (MLVA) and gene identification have been useful for epidemiological study of several bacterial species. To develop a genotyping method, the genome sequence of Staphylococcus chromogenes MU970 was analysed. The analysis showed nine virulence genes described in Staphylococcus aureus. The MLVA was developed using four loci identified in the genome of S. chromogenes MU970. This genotyping method was examined in 23 strains of CNS isolated from goat mastitis. The rate of discrimination for MLVA was 0.8893, and the highest rates of discrimination per the index of Simpson and Hunter-Gaston were 0.926 and 0.968 for the locus 346_06, respectively. The virulence genes were present in all strains of S. chromogenes but not in other CNS. The genotyping method presented in this paper is a viable and easy method for typifying CNS isolates from mastitis cases in different regions and is an ideal mean of tracking this disease.

Keywords

  • genotyping
  • mastitis in goats
  • MLVA
  • VNTR
access type Open Access

Screening and Identification of Trichoderma Strains Isolated from Natural Habitats with Potential to Cellulose and Xylan Degrading Enzymes Production

Published Online: 30 Jun 2018
Page range: 181 - 190

Abstract

Abstract

A total of 123 Trichoderma strains were isolated from different habitats and tested for their ability to degrade cellulose and xylan by simple plate screening method. Among strains, more than 34 and 45% respectively, exhibited higher cellulolytic and xylanolytic activity, compared to the reference strain T. reesei QM 9414. For strains efficiently degrading cellulose, a highest enzyme activity was confirmed using filter paper test, and it resulted in a range from 1.01 to 7.15 FPU/ml. Based on morphological and molecular analysis, the isolates were identified as Trichoderma. The most frequently identified strains belonged to Trichoderma harzianum species. Among all strains, the most effective in degradation of cellulose and xylose was T. harzianum and T. virens, especially those isolated from forest wood, forest soil or garden and mushroom compost. The results of this work confirmed that numerous strains from the Trichoderma species have high cellulose and xylan degradation potential and could be useful for lignocellulose biomass conversion e.g. for biofuel production.

Keywords

  • microorganisms screening
  • species
  • lignocellulose biomass
  • cellulolytic activity
  • xylanolytic activity
access type Open Access

The Heavy-Metal Resistance Determinant of Newly Isolated Bacterium from a Nickel-Contaminated Soil in Southwest Slovakia

Published Online: 30 Jun 2018
Page range: 191 - 201

Abstract

Abstract

A bacterial isolate MR-CH-I2 [KC809939] isolated from soil contaminated mainly by high nickel concentrations in southwest Slovakia was previously found carrying nccA-like heavy-metal resistance determinant, marked as MR-CH-I2-HMR [KF218096]. According to phylogenetic analysis of short (696 bp) 16S rDNA (16S rRNA) sequences this bacterium was tentatively assigned to Uncultured beta proteobacterium clone GC0AA7ZA05PP1 [JQ913301]. nccA-like gene product was on the same base of its partial (581 bp) sequences tentatively assigned to CzcA family heavy metal efflux pump [YP_001899332] from Ralstonia picketii 12J with 99% similarity. In this study the bacterium MR-CH-I2 and its heavy-metal resistance determinant were more precisely identified. This bacterial isolate was on the base of phylogenetic analysis of almost the whole (1,500 bp) 16S rDNA (16S rRNA) sequence, MR-CH-I2 [MF102046], and sequence for gyrB gene and its product respectively, MR-CH-I2-gyrB [MF134666], assigned to R. picketii 12J [CP001068] with 99 and 100% similarities, respectively. In addition, the whole nccA-like heavy-metal resistance gene sequence (3,192 bp), marked as MR-CH-I2-nccA [KR476581], was obtained and on the base of phylogenetic analysis its assignment was confirmed to MULTISPECIES: cation efflux system protein CzcA [WP_004635342] from Burkholderiaceae with 98% similarity. Furthermore, although the bacterium carried one high molecular plasmid of about 50 kb in size, nccA-like gene was not located on this plasmid. Finally, the results from RT-PCR analysis showed that MR-CH-I2-nccA gene was significantly induced only by the addition of nickel.

Keywords

  • 16S rRNA (16S rDNA)
  • DNA gyrase subunit B
  • heavy-metal resistance determinant
  • high molecular plasmid
  • nickel-contaminated soil
  • RT-qPCR
access type Open Access

Distribution of Cell Envelope Proteinases Genes among Polish Strains of Lactobacillus helveticus

Published Online: 30 Jun 2018
Page range: 203 - 211

Abstract

Abstract

Most of the lactic acid bacteria (LAB) are able to grow in milk mainly due to the activity of a complex and well-developed proteolytic system. Cell envelope-associated proteinases (CEPs) begin casein hydrolysis and allow for releasing the peptides, enclosed in the structure of native milk proteins that are essential for growth of Lactobacillus helveticus. The biodiversity of genes encoding CEPs among L. helveticus strains can have an effect on some technological parameters such as acid production, bacterial growth rate in milk as well as liberation of biologically active peptides. The study reveals significant differences in the presence of various variants of CEPs encoding genes among ten novel Polish strains and indicates the intraspecific diversity exhibited by L. helveticus. In terms of distribution of CEPs genes, four different genetic profiles were found among the microorganisms analyzed. Furthermore, the strains exhibited also various levels of proteolytic activity. Molecular analysis revealed that prtH3 is the most abundant CEPs-encoding gene among the strains investigated. The results indicate also that ecological niche and environmental conditions might affect proteolytic properties of L. helveticus strains. The greatest variety in terms of quantity of the detected CEP encoding genes was noticed in L. helveticus 141, T105 and T104 strains. In these strains, the combination of three nucleotide gene sequences (prtH/prtH2/prtH3) was identified. Interestingly, T104 and T105 exhibited the highest proteolytic activity and also the fastest dynamic of milk acidification among the tested strains of L. helveticus.

Keywords

  • cell envelope proteinases (CEPs)
  • proteolytic activity
access type Open Access

The Usefulness of Chromogenic Media for Qualitative and Semi-Quantitative Diagnostic of Urinary Tract Infections

Published Online: 30 Jun 2018
Page range: 213 - 218

Abstract

Abstract

The aim of this study was to evaluate the usefulness of chromogenic media for isolation of bacteria from urine and direct identification of UTI pathogens. A total of 100 urine specimens were inoculated on blood agar and MacConkey agar as a reference method and on the following media to be tested: chromID® CPS® Elite (CPSE, bioMérieux), CHROMagarTM Orientation (BioMaxima), BD CHROMagar Orientation Medium (ORI, Becton Dickinson), CHROMagarTM Orientation (ORIE, Graso) and Brillance UTI Clarity Agar (UTI C, Oxoid). After a 24-hour incubation period, 47 Gram-positive cocci and 62 Gram-negative rods were observed. The specificity and sensitivity of all chromogenic media was 97.3% and 93.5% respectively for qualitative diagnostic; and 81.9% and 81.3% respectively for semi-quantitative diagnostic. The mean PPV and NPV of the chromogenic media were 98.7% and 87.7% for qualitative UTI diagnostic, and 90.9% and 71.9% respectively for semi-quantitative diagnostic.

Keywords

  • chromogenic media
  • qualitative and semi-quantitative microbiological diagnostic
  • urinary tract infections (UTI)

short-communication

access type Open Access

Identification of Pathogenicity of Yersinia enterocolitica in Pig Tonsils Using the Real-Time PCR

Published Online: 30 Jun 2018
Page range: 219 - 222

Abstract

Abstract

The application of DNA-based methods enables to identify Yersinia enterocolitica carrying the ail-gene with a greater sensitivity compared to culture methods and biochemical tests used for detection of pathogenic Y. enterocolitica in animal and food samples. In this study, 100 samples of pig tonsils were examined, among which 17 were positive for the ail gene. Additionally, biochemical tests and RT-PCR showed that nine Y. enterocolitica isolates carried the ail-gene. Two Y. enterocolitica isolates of 1A biotype had the ail gene. The results demonstrated the usefulness of RT-PCR method applied for detection of potentially pathogenic, possessing the ail gene Y. enterocolitica in the material examined.

Keywords

  • RT-PCR
  • pathogen specific gene ()
  • biochemical testing
  • biotyping
access type Open Access

Global Transcriptome Changes of Biofilm-Forming Staphylococcus epidermidis Responding to Total Alkaloids of Sophorea alopecuroides

Published Online: 30 Jun 2018
Page range: 223 - 226

Abstract

Abstract

Transcriptome changes of biofilm-forming Staphylococcus epidermidis response to total alkaloids of Sophorea alopecuroides was observed. Bioinformatic analyses were further used to compare the differential gene expression between control and the treated samples. It was found that 282 genes were differentially expressed, with 92 up-regulated and 190 down-regulated. These involved down-regulation of the sulfur metabolism pathway. It was suggested that inhibitory effects on Staphylococcus epidermidis and its biofilm formation of the total alkaloids of S. alopecuroides was mainly due to the regulation of the sulfur metabolism pathways of S. epidermidis.

Keywords

  • sulfur metabolism
  • total alkaloids of
  • transcriptome
access type Open Access

Sero-epidemiology and Risk Factor Analysis of Measles Among Children in Pakistan

Published Online: 30 Jun 2018
Page range: 227 - 231

Abstract

Abstract

Comparative cross sectional study was conducted on blood samples (n = 231) collected from children of 1 to 10 years of age in Punjab Pakistan through convenient sampling method. Indirect haemagglutination assay (IHA) was standardized and used for serodiagnosis and evaluation of humoral immunity against measles. Associated risk factors including age, gender, locale, and vaccination status were analyzed. Geometric mean titre (GMT) of vaccinated individuals was significantly higher (p < 0.001) than that of non-vaccinated individuals showing that IHA titre of vaccinated individuals was a measure of humoral immune response; whereas, in case of non-vaccinated individuals an indicative of exposure to the measles infection.

Keywords

  • measles
  • sero-epidemiology
  • geometric mean titre
  • IHA
access type Open Access

Seroprevalence of Selected Zoonotic Agents among Hunters from Eastern Poland

Published Online: 30 Jun 2018
Page range: 233 - 236

Abstract

Abstract

The aim of our study was the collection of seroprevalence data for Toxoplasma gondii, Coxiella burnetii, Trichinella spp., and Francisella tularensis from hunters in Lublin Province. The antibodies against T. gondii and C. burnetii were recorded in 38.5% and 16.2% of the sera, respectively. 4.05% of the sera were seropositive for both T. gondii and C. burnetii. None of the sera tested reacted positively with F. tulariensis or Trichinella spp. Seroprevalence of T. gondii and C. burnetii is common among the hunters from Lublin Province. It seems reasonable to undertake similar research among hunters from other regions of eastern Poland.

Keywords

  • spp.
  • hunters
access type Open Access

New Gene Responsible for Resistance of Clinical Corynebacteria to Macrolide, Lincosamide and Streptogramin B

Published Online: 30 Jun 2018
Page range: 237 - 240

Abstract

Abstract

The subject of the study was phenotypic marking of the antibiotic susceptibility and MLSB resistance mechanism in Corynebacterium spp. isolated from human skin (18 isolates) and from clinical materials (19 isolates). The strains were tested for the presence of the erm(A), erm(B), erm(C), erm(X), lnu(A), msr(A), msr(B) and mph(C) genes. Clinical isolates showed wide resistance to antibiotics. In 89% clinical isolates and 72% skin microbiota a constitutive type of MLSB resistance was found. In 12 clinical isolates the erm(C) gene was detected-eight of which had erm(X) as well as erm(C), two harboured erm(X), erm(C) and erm(A) and two demonstrated only erm(C).

Keywords

  • spp.
  • (C)
  • MLS
  • resistance genes
access type Open Access

Development and Evaluation of a Latex Agglutination Test for the Identification of Francisella tularensis Subspecies Pathogenic for Human

Published Online: 30 Jun 2018
Page range: 241 - 244

Abstract

Abstract

Francisella tularensis are highly infectious bacteria causing a zoonotic disease called tularemia. Identification of this bacterium is based on antigen detection or PCR. The paper presents a latex agglutination test (LAT) for rapid identification of clinically relevant F. tularensis subspecies. The test can be performed within three minutes with live or inactivated bacteria. The possibility to test the inactivated samples reduces the risk of laboratory acquired infection and allows performing the test under BSL-2 conditions.

Keywords

  • identification
  • latex agglutination test
  • tularemia
  • zoonosis
15 Articles

mini-review

access type Open Access

Non-antibiotics, Efflux Pumps and Drug Resistance of Gram-negative Rods

Published Online: 30 Jun 2018
Page range: 129 - 135

Abstract

Abstract

Non-antibiotic medicinal products consist of drugs with diverse activity against bacteria. Many non-antibiotics demonstrate direct anti-bacterial activity against Gram-positive cocci. The activity observed against Gram-negative rods is much lower and non-antibiotics primarily from the following groups: non-steroidal anti-inflammatory drugs, cardiovascular and antidepressant medicinal products demonstrate this activity. It has been shown that the low activity of some non-antibiotics or the absence of activity against Gram-negative rods is related, among other things, to the extrusion of these compounds from bacterial cells by multi-drug resistance efflux pumps. Substrates for the resistance-nodulation-division efflux systems include the following non-antibiotics: salicylate, diclofenac, ibuprofen, mefenamic acid, naproxen, amitriptyline, alendronate sodium, nicergoline, and ticlopidine. In addition, interactions between non-antibiotics and multi-drug resistance efflux pumps have been observed. It has also been revealed that depending on the concentration, salicylate induces expression of multi-drug resistance efflux pumps in Escherichia coli, Salmonella enterica subsp. enterica serotype Typhimurium, and Burkholderia cenocepacia. However, salicylate does not affect the expression of the resistance-nodulation-division efflux systems in Stenotrophomonas maltophilia and Acinetobacter baumannii. Most importantly, there were no effects of medicinal products containing some non-antibiotic active substances, except salicylate, as substrates of multi-drug resistance efflux pumps, on the induction of Gram-negative rod resistance to quinolones.

Keywords

  • MDR efflux pumps
  • antibiotic resistance
  • non-antibiotics
access type Open Access

Bacteriological, Clinical and Virulence Aspects of Aeromonas-associated Diseases in Humans

Published Online: 30 Jun 2018
Page range: 137 - 150

Abstract

Abstract

Aeromonads have been isolated from varied environmental sources such as polluted and drinking water, as well as from tissues and body fluids of cold and warm-blooded animals. A phenotypically and genotypically heterogenous bacteria, aeromonads can be successfully identified by ribotyping and/or by analysing gyrB gene sequence, apart from classical biochemical characterization. Aeromonads are known to cause scepticemia in aquatic organisms, gastroenteritis and extraintestinal diseases such as scepticemia, skin, eye, wound and respiratory tract infections in humans. Several virulence and antibiotic resistance genes have been identified and isolated from this group, which if present in their mobile genetic elements, may be horizontally transferred to other naive environmental bacteria posing threat to the society. The extensive and indiscriminate use of antibiotics has given rise to many resistant varieties of bacteria. Multidrug resistance genes, such as NDM1, have been identified in this group of bacteria which is of serious health concern. Therefore, it is important to understand how antibiotic resistance develops and spreads in order to undertake preventive measures. It is also necessary to search and map putative virulence genes of Aeromonas for fighting the diseases caused by them. This review encompasses current knowledge of bacteriological, environmental, clinical and virulence aspects of the Aeromonas group and related diseases in humans and other animals of human concern.

Keywords

  • aeromonad
  • diarrhea
  • multi-drug
  • resistance
  • virulence
access type Open Access

Brucella – Virulence Factors, Pathogenesis and Treatment

Published Online: 30 Jun 2018
Page range: 151 - 161

Abstract

Abstract

Brucellae are Gram-negative, small rods infecting mammals and capable of causing disease called brucellosis. The infection results in abortion and sterility in domestic animals (sheeps, pigs, rams etc). Especially dangerous for humans are: Brucella melitensis, Brucella suis, Brucella abortus, and Brucella canis that trigger unspecific symptoms (flu-like manifestation). Brucella rods are introduced via host cells, by inhalation, skin abrasions, ingestion or mucosal membranes. The most important feature of Brucella is the ability to survive and multiply within both phagocytic and non-phagocytic cells. Brucella does not produce classical virulence factors: exotoxin, cytolisins, exoenzymes, plasmids, fimbria, and drug resistant forms. Major virulence factors are: lipopolysaccharide (LPS), T4SS secretion system and BvrR/BvrS system, which allow interaction with host cell surface, formation of an early, late BCV (Brucella Containing Vacuole) and interaction with endoplasmic reticulum (ER) when the bacteria multiply. The treatment of brucellosis is based on two-drug therapy, the most common combinations of antibiotics are: doxycycline with rifampicin or fluoroquinolones with rifampicin. Currently, also other methods are used to disrupt Brucella intracellular replication (tauroursodeoxycholic acid or ginseng saponin fraction A).

Keywords

  • endoplasmic reticulum
  • macrophage
  • replication
  • virulence factors

original-paper

access type Open Access

Isolation of Bacteriocin-producing Staphylococcus spp. Strains from Human Skin Wounds, Soft Tissue Infections and Bovine Mastitis

Published Online: 30 Jun 2018
Page range: 163 - 170

Abstract

Abstract

A collection of 206 Staphylococcus spp. isolates was investigated for their ability to produce compounds exhibiting antistaphylococcal activity. This group included Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus xylosus strains recovered from bovine mastitis (n = 158) and human skin wounds and soft tissues infections (n = 48). Production of substances with antimicrobial activity was observed in six strains. Five of them were recovered from bovine mastitis, and one was isolated from the infected human skin wound. Three of the six antimicrobials produced by the different strains showed substantial loss of antimicrobial activity upon treatment with proteolytic enzymes, which suggests their peptidic structure. Additional studies have shown that one of the putative bacteriocins was efficiently secreted to the liquid medium, facilitating its large-scale production and isolation. The peptide produced by the M2B strain exhibited promising activity; however, against narrow spectrum of Staphylococcus spp. clinical and animal isolates. Growth inhibition was observed only in the case of 13 (including nine S. aureus, three S. xylosus and one S. epidermidis strains) out of 206 strains tested. Important advantage of the produced agent was its high thermal stability. Fifteen minutes of incubation at 90°C did not affect its antimicrobial potential. The highest efficiency of production of the agent was demonstrated in TSB medium after 24 hours at 37°C. The researches revealed that ability to production of bacteriocin among staphylococci is not very common. Only one (S. xylosus strain assigned as M2B) out of 206 strains tested produced satisfactory amounts of antistaphylococcal bacteriocin. In spite of that, we would encourage other researchers for investigation of their collections of Staphylococcus spp. isolates towards selection strains producing antimicrobial agents.

Keywords

  • antimicrobial peptides
  • antistaphylococcal agents
access type Open Access

Genetic Analysis Method for Staphylococcus chromogenes Associated with Goat Mastitis

Published Online: 30 Jun 2018
Page range: 171 - 180

Abstract

Abstract

Mastitis in goats is mainly caused by coagulase-negative Staphylococcus (CNS). The identification methods for this group are based on evaluating the expression of phenotypic characteristics such as the ability to metabolize various substrates; however, this is disadvantageous as these methods are dependent on gene expression. In recent years, genotyping methods such as the Multiple Locus Variable-Number Tandem Repeat Analysis (MLVA) and gene identification have been useful for epidemiological study of several bacterial species. To develop a genotyping method, the genome sequence of Staphylococcus chromogenes MU970 was analysed. The analysis showed nine virulence genes described in Staphylococcus aureus. The MLVA was developed using four loci identified in the genome of S. chromogenes MU970. This genotyping method was examined in 23 strains of CNS isolated from goat mastitis. The rate of discrimination for MLVA was 0.8893, and the highest rates of discrimination per the index of Simpson and Hunter-Gaston were 0.926 and 0.968 for the locus 346_06, respectively. The virulence genes were present in all strains of S. chromogenes but not in other CNS. The genotyping method presented in this paper is a viable and easy method for typifying CNS isolates from mastitis cases in different regions and is an ideal mean of tracking this disease.

Keywords

  • genotyping
  • mastitis in goats
  • MLVA
  • VNTR
access type Open Access

Screening and Identification of Trichoderma Strains Isolated from Natural Habitats with Potential to Cellulose and Xylan Degrading Enzymes Production

Published Online: 30 Jun 2018
Page range: 181 - 190

Abstract

Abstract

A total of 123 Trichoderma strains were isolated from different habitats and tested for their ability to degrade cellulose and xylan by simple plate screening method. Among strains, more than 34 and 45% respectively, exhibited higher cellulolytic and xylanolytic activity, compared to the reference strain T. reesei QM 9414. For strains efficiently degrading cellulose, a highest enzyme activity was confirmed using filter paper test, and it resulted in a range from 1.01 to 7.15 FPU/ml. Based on morphological and molecular analysis, the isolates were identified as Trichoderma. The most frequently identified strains belonged to Trichoderma harzianum species. Among all strains, the most effective in degradation of cellulose and xylose was T. harzianum and T. virens, especially those isolated from forest wood, forest soil or garden and mushroom compost. The results of this work confirmed that numerous strains from the Trichoderma species have high cellulose and xylan degradation potential and could be useful for lignocellulose biomass conversion e.g. for biofuel production.

Keywords

  • microorganisms screening
  • species
  • lignocellulose biomass
  • cellulolytic activity
  • xylanolytic activity
access type Open Access

The Heavy-Metal Resistance Determinant of Newly Isolated Bacterium from a Nickel-Contaminated Soil in Southwest Slovakia

Published Online: 30 Jun 2018
Page range: 191 - 201

Abstract

Abstract

A bacterial isolate MR-CH-I2 [KC809939] isolated from soil contaminated mainly by high nickel concentrations in southwest Slovakia was previously found carrying nccA-like heavy-metal resistance determinant, marked as MR-CH-I2-HMR [KF218096]. According to phylogenetic analysis of short (696 bp) 16S rDNA (16S rRNA) sequences this bacterium was tentatively assigned to Uncultured beta proteobacterium clone GC0AA7ZA05PP1 [JQ913301]. nccA-like gene product was on the same base of its partial (581 bp) sequences tentatively assigned to CzcA family heavy metal efflux pump [YP_001899332] from Ralstonia picketii 12J with 99% similarity. In this study the bacterium MR-CH-I2 and its heavy-metal resistance determinant were more precisely identified. This bacterial isolate was on the base of phylogenetic analysis of almost the whole (1,500 bp) 16S rDNA (16S rRNA) sequence, MR-CH-I2 [MF102046], and sequence for gyrB gene and its product respectively, MR-CH-I2-gyrB [MF134666], assigned to R. picketii 12J [CP001068] with 99 and 100% similarities, respectively. In addition, the whole nccA-like heavy-metal resistance gene sequence (3,192 bp), marked as MR-CH-I2-nccA [KR476581], was obtained and on the base of phylogenetic analysis its assignment was confirmed to MULTISPECIES: cation efflux system protein CzcA [WP_004635342] from Burkholderiaceae with 98% similarity. Furthermore, although the bacterium carried one high molecular plasmid of about 50 kb in size, nccA-like gene was not located on this plasmid. Finally, the results from RT-PCR analysis showed that MR-CH-I2-nccA gene was significantly induced only by the addition of nickel.

Keywords

  • 16S rRNA (16S rDNA)
  • DNA gyrase subunit B
  • heavy-metal resistance determinant
  • high molecular plasmid
  • nickel-contaminated soil
  • RT-qPCR
access type Open Access

Distribution of Cell Envelope Proteinases Genes among Polish Strains of Lactobacillus helveticus

Published Online: 30 Jun 2018
Page range: 203 - 211

Abstract

Abstract

Most of the lactic acid bacteria (LAB) are able to grow in milk mainly due to the activity of a complex and well-developed proteolytic system. Cell envelope-associated proteinases (CEPs) begin casein hydrolysis and allow for releasing the peptides, enclosed in the structure of native milk proteins that are essential for growth of Lactobacillus helveticus. The biodiversity of genes encoding CEPs among L. helveticus strains can have an effect on some technological parameters such as acid production, bacterial growth rate in milk as well as liberation of biologically active peptides. The study reveals significant differences in the presence of various variants of CEPs encoding genes among ten novel Polish strains and indicates the intraspecific diversity exhibited by L. helveticus. In terms of distribution of CEPs genes, four different genetic profiles were found among the microorganisms analyzed. Furthermore, the strains exhibited also various levels of proteolytic activity. Molecular analysis revealed that prtH3 is the most abundant CEPs-encoding gene among the strains investigated. The results indicate also that ecological niche and environmental conditions might affect proteolytic properties of L. helveticus strains. The greatest variety in terms of quantity of the detected CEP encoding genes was noticed in L. helveticus 141, T105 and T104 strains. In these strains, the combination of three nucleotide gene sequences (prtH/prtH2/prtH3) was identified. Interestingly, T104 and T105 exhibited the highest proteolytic activity and also the fastest dynamic of milk acidification among the tested strains of L. helveticus.

Keywords

  • cell envelope proteinases (CEPs)
  • proteolytic activity
access type Open Access

The Usefulness of Chromogenic Media for Qualitative and Semi-Quantitative Diagnostic of Urinary Tract Infections

Published Online: 30 Jun 2018
Page range: 213 - 218

Abstract

Abstract

The aim of this study was to evaluate the usefulness of chromogenic media for isolation of bacteria from urine and direct identification of UTI pathogens. A total of 100 urine specimens were inoculated on blood agar and MacConkey agar as a reference method and on the following media to be tested: chromID® CPS® Elite (CPSE, bioMérieux), CHROMagarTM Orientation (BioMaxima), BD CHROMagar Orientation Medium (ORI, Becton Dickinson), CHROMagarTM Orientation (ORIE, Graso) and Brillance UTI Clarity Agar (UTI C, Oxoid). After a 24-hour incubation period, 47 Gram-positive cocci and 62 Gram-negative rods were observed. The specificity and sensitivity of all chromogenic media was 97.3% and 93.5% respectively for qualitative diagnostic; and 81.9% and 81.3% respectively for semi-quantitative diagnostic. The mean PPV and NPV of the chromogenic media were 98.7% and 87.7% for qualitative UTI diagnostic, and 90.9% and 71.9% respectively for semi-quantitative diagnostic.

Keywords

  • chromogenic media
  • qualitative and semi-quantitative microbiological diagnostic
  • urinary tract infections (UTI)

short-communication

access type Open Access

Identification of Pathogenicity of Yersinia enterocolitica in Pig Tonsils Using the Real-Time PCR

Published Online: 30 Jun 2018
Page range: 219 - 222

Abstract

Abstract

The application of DNA-based methods enables to identify Yersinia enterocolitica carrying the ail-gene with a greater sensitivity compared to culture methods and biochemical tests used for detection of pathogenic Y. enterocolitica in animal and food samples. In this study, 100 samples of pig tonsils were examined, among which 17 were positive for the ail gene. Additionally, biochemical tests and RT-PCR showed that nine Y. enterocolitica isolates carried the ail-gene. Two Y. enterocolitica isolates of 1A biotype had the ail gene. The results demonstrated the usefulness of RT-PCR method applied for detection of potentially pathogenic, possessing the ail gene Y. enterocolitica in the material examined.

Keywords

  • RT-PCR
  • pathogen specific gene ()
  • biochemical testing
  • biotyping
access type Open Access

Global Transcriptome Changes of Biofilm-Forming Staphylococcus epidermidis Responding to Total Alkaloids of Sophorea alopecuroides

Published Online: 30 Jun 2018
Page range: 223 - 226

Abstract

Abstract

Transcriptome changes of biofilm-forming Staphylococcus epidermidis response to total alkaloids of Sophorea alopecuroides was observed. Bioinformatic analyses were further used to compare the differential gene expression between control and the treated samples. It was found that 282 genes were differentially expressed, with 92 up-regulated and 190 down-regulated. These involved down-regulation of the sulfur metabolism pathway. It was suggested that inhibitory effects on Staphylococcus epidermidis and its biofilm formation of the total alkaloids of S. alopecuroides was mainly due to the regulation of the sulfur metabolism pathways of S. epidermidis.

Keywords

  • sulfur metabolism
  • total alkaloids of
  • transcriptome
access type Open Access

Sero-epidemiology and Risk Factor Analysis of Measles Among Children in Pakistan

Published Online: 30 Jun 2018
Page range: 227 - 231

Abstract

Abstract

Comparative cross sectional study was conducted on blood samples (n = 231) collected from children of 1 to 10 years of age in Punjab Pakistan through convenient sampling method. Indirect haemagglutination assay (IHA) was standardized and used for serodiagnosis and evaluation of humoral immunity against measles. Associated risk factors including age, gender, locale, and vaccination status were analyzed. Geometric mean titre (GMT) of vaccinated individuals was significantly higher (p < 0.001) than that of non-vaccinated individuals showing that IHA titre of vaccinated individuals was a measure of humoral immune response; whereas, in case of non-vaccinated individuals an indicative of exposure to the measles infection.

Keywords

  • measles
  • sero-epidemiology
  • geometric mean titre
  • IHA
access type Open Access

Seroprevalence of Selected Zoonotic Agents among Hunters from Eastern Poland

Published Online: 30 Jun 2018
Page range: 233 - 236

Abstract

Abstract

The aim of our study was the collection of seroprevalence data for Toxoplasma gondii, Coxiella burnetii, Trichinella spp., and Francisella tularensis from hunters in Lublin Province. The antibodies against T. gondii and C. burnetii were recorded in 38.5% and 16.2% of the sera, respectively. 4.05% of the sera were seropositive for both T. gondii and C. burnetii. None of the sera tested reacted positively with F. tulariensis or Trichinella spp. Seroprevalence of T. gondii and C. burnetii is common among the hunters from Lublin Province. It seems reasonable to undertake similar research among hunters from other regions of eastern Poland.

Keywords

  • spp.
  • hunters
access type Open Access

New Gene Responsible for Resistance of Clinical Corynebacteria to Macrolide, Lincosamide and Streptogramin B

Published Online: 30 Jun 2018
Page range: 237 - 240

Abstract

Abstract

The subject of the study was phenotypic marking of the antibiotic susceptibility and MLSB resistance mechanism in Corynebacterium spp. isolated from human skin (18 isolates) and from clinical materials (19 isolates). The strains were tested for the presence of the erm(A), erm(B), erm(C), erm(X), lnu(A), msr(A), msr(B) and mph(C) genes. Clinical isolates showed wide resistance to antibiotics. In 89% clinical isolates and 72% skin microbiota a constitutive type of MLSB resistance was found. In 12 clinical isolates the erm(C) gene was detected-eight of which had erm(X) as well as erm(C), two harboured erm(X), erm(C) and erm(A) and two demonstrated only erm(C).

Keywords

  • spp.
  • (C)
  • MLS
  • resistance genes
access type Open Access

Development and Evaluation of a Latex Agglutination Test for the Identification of Francisella tularensis Subspecies Pathogenic for Human

Published Online: 30 Jun 2018
Page range: 241 - 244

Abstract

Abstract

Francisella tularensis are highly infectious bacteria causing a zoonotic disease called tularemia. Identification of this bacterium is based on antigen detection or PCR. The paper presents a latex agglutination test (LAT) for rapid identification of clinically relevant F. tularensis subspecies. The test can be performed within three minutes with live or inactivated bacteria. The possibility to test the inactivated samples reduces the risk of laboratory acquired infection and allows performing the test under BSL-2 conditions.

Keywords

  • identification
  • latex agglutination test
  • tularemia
  • zoonosis

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