<Emphasis Type="Italic">Lactobacillus plantarum</Emphasis> as a Probiotic Potential from Kouzeh Cheese (Traditional Iranian Cheese) and Its Antimicrobial Activity

The aim of this study is to isolate and identify Lactobacillus plantarum isolates from traditional cheese, Kouzeh, and evaluate their antimicrobial activity against some food pathogens. In total, 56 lactic acid bacteria were isolated by morphological and biochemical methods, 12 of which were identified as Lactobacillus plantarum by biochemical method and 11 were confirmed by molecular method. For analyzing the antimicrobial activity of these isolates properly, diffusion method was performed. The isolates were identified by 318 bp band dedicated for L. plantarum. The isolated L. plantarum represented an inhibitory activity against four of the pathogenic bacteria and showed different inhibition halos against each other. The larger halos were observed against Staphylococcus aureus and Staphylococcus epidermidis (15 ± 0.3 and 14.8 ± 0.7 mm, respectively). The inhibition halo of Escherichia coli was smaller than that of other pathogen and some L. plantarum did not show any inhibitory activity against E. coli, which were resistant to antimicrobial compounds produced by L. plantarum. The isolated L. plantarum isolates with the antimicrobial activity in this study had strong probiotic properties. These results indicated the nutritional value of Kouzeh cheese and usage of the isolated isolates as probiotic strains.     

Antimicrobial properties of endophytic actinomycetes isolated from <Emphasis Type="Italic">Combretum latifolium</Emphasis> Blume,a medicinal shrub from Western Ghats of India

Endophytic actinomycetes were isolated from Combretum latifolium Blume (Combretaceae),Western Ghats of Southern India and identified by its characteristic culture morphology and molecular analysis of 16S rRNA gene sequences. In this survey of endophytic actinomycetes, a total of 117 isolates representing 9 different genera of endophytic actinomycetes were obtained using four different isolation media and several of them seemed to be novel taxa. Streptomyces genera (35%) was the most frequently isolated strains, followed by Nocordiopsis (17%) and Micromonospora (13%). ISP-4 medium recovered more isolates (47%) when compared to rest of the media used. Preliminary antibacterial activity of the isolates was carried out by confrontation test. Ethyl acetate fraction of selected isolates in disc diffusion assay exhibited broad spectrum antimicrobial activity against test human pathogens. All Streptomyces spp. strains displayed significant antimicrobial activity against test pathogens. Strain CLA-66 and CLA-68 which are Nocordipsis spp. inhibited both bacterial and fungal pathogens where as other isolates inhibited atleast three test human pathogens in disc diffusion assay. Antimicrobial screening of endophytic actinomycetes from this host may represent a unique potential niche for antimicrobial compounds of industrial and pharmaceutical applications. This work is the first comprehensive report on incidence of potential endophytic actinomycetes inhabiting C. latifolium Blume.     

Diversity of Heterotrophic Halophilic Bacteria Isolated from Coastal Solar Salterns,Bulgaria and Their Ability to Synthesize Bioactive Molecules with Biotechnological Impact

Investigations on the microbial life in several coastal solar salterns have revealed the presence of novel organisms and synthesis of unusual molecules active in extreme conditions which might be useful in different biotechnological industries. Biodiversity of heterotrophic aerobic bacteria isolated from two salterns, Pomorie salterns and Burgas salterns located at Burgas Bay, Black Sea coast, Bulgaria, as well as ability of the isolates to synthesize biotechnologically valuable compounds were investigated. The results revealed high taxonomic and metabolic bacterial diversity—we isolated 20 morphologically different moderately halophilic and two halotolerant strains affiliated with 11 species from eight genera referred to the phyla Proteobacteria, Firmicutes, and Actinobacteria. Gram-negative bacteria belonged to the genera Halomonas, Chromohalobacter, Salinivibrio, Cobetia, and Nesiotobacter, and gram-positive strains were representatives of the genera Virgibacillus, Salinicoccus, and Brevibacterium. All isolates were found to be alkalitolerant, and 41% of them were psychrotolerant. The strains degraded nine of the tested 18 substrates; polygalacturonase, catalase, phytase, and lipase producers were predominant. This is the first reported detection of xanthan lyase, gellan lyase, arabinase, and phytase activities in halophilic bacteria. Nine of the strains belonging to five different genera were found to produce exopolysaccharides (EPS). The highest level of EPS was observed in Chromohalobacter canadensis strain 28. More than a half of the strains displayed antimicrobial activity against one to five test bacteria and yeasts. The present study is the first report on halophilic bacteria isolated from salterns at the Black Sea coast indicating that the investigated area is an untapped resource of halophilic bacteria with biotechnological potential.     

Antibiotic activity of bacterial endobionts of basidiomycete fruit bodies

Bacterial strains (93 isolates) capable of growth on full-strength nutrient media were isolated from 86 fungal fruit bodies collected in the Moscow region. Antimicrobial activity of the endobiont isolates against 12 bacterial and fungal test strains (including drug-resistant ones) was studied in submerged cultures. Most of the strains (84.9%) were found to produce antibiotic compounds with different antimicrobial properties, including antifungal activity in 18.3% of the strains. Morphological characteristics and analysis of the 16S rRNA gene sequences were used to determine the taxonomic position of 16 bacterial strains of the following 10 species: Bacillus subtilis, Ewingella americana, Pseudomonas sp., Stenotrophomonas maltophilia, as well as Achromobacter spanius, B. licheniformis, Hafnia paralvei, Micrococcus terreus, Nocardia coeliaca, and St. rhizophila, which have not been previously known to be endobionts of basidiomycete fruit bodies. Antimicrobial activity of A. spanius, E. americana, H. paralvei, M. terreus, N. coeliaca, and St. rhizophila has not been reported previously. Complex mechanisms of symbiotic relations between fungi and bacteria, including those associated with antibiotic formation, probably developed in the course of co-evolution.     

Phylogeny and bioactivity of epiphytic Gram-positive bacteria isolated from three co-occurring antarctic macroalgae

Marine macroalgae are emerging as an untapped source of novel microbial diversity and, therefore, of new bioactive secondary metabolites. This study was aimed at assessing the diversity and antimicrobial activity of the culturable Gram-positive bacteria associated with the surface of three co-occurring Antarctic macroalgae. Specimens of Adenocystis utricularis (brown alga), Iridaea cordata (red alga) and Monostroma hariotii (green alga) were collected from the intertidal zone of King George Island, Antarctica. Gram-positive bacteria were investigated by cultivation-based methods and 16S rRNA gene sequencing, and screened for antimicrobial activity against a panel of pathogenic microorganisms. Isolates were found to belong to 12 families, with a dominance of Microbacteriaceae and Micrococcaceae. Seventeen genera of Actinobacteria and 2 of Firmicutes were cultured from the three macroalgae, containing 29 phylotypes. Three phylotypes within Actinobacteria were regarded as potentially novel species. Sixteen isolates belonging to the genera Agrococcus, Arthrobacter, Micrococcus, Pseudarthrobacter, Pseudonocardia, Sanguibacter, Staphylococcus, Streptomyces and Tessaracoccus exhibited antibiotic activity against at least one of the indicator strains. The bacterial phylotype composition was distinct among the three macroalgae species, suggesting that these macroalgae host species-specific Gram-positive associates. The results highlight the importance of Antarctic macroalgae as a rich source of Gram-positive bacterial diversity and potentially novel species, and a reservoir of bacteria producing biologically active compounds with pharmacological potential.     

Characterization of bacterial composition and diversity in a long-term petroleum contaminated soil and isolation of high-efficiency alkane-degrading strains using an improved medium

Bacterial community and diversity in a long-term petroleum-contaminated soil of an oilfield were characterized using 16S rRNA gene-based Illumina MiSeq high-throughput sequencing. Results indicated that Proteobacteria (49.11%) and Actinobacteria (24.24%) were the most dominant phyla, and the most abundant genera were Pseudoxanthomonas (8.47%), Luteimonas (3.64%), Alkanindiges (9.76%), Acinetobacter (5.26%) and Agromyces (8.56%) in the soil. Meanwhile a series of cultivations were carried out for isolation of alkane degraders from petroleum-contaminated soil with gellan gum and agar as gelling agents. And the isolates were classified by their 16S rRNA genes. Nine of the isolates including Enterobacter, Pseudomonas,Acinetobacter, Rhizobium, Bacillus, Sphingomonas, Paenibacillus, Variovorax and Rhodococcus showed strong biodegradability of alkane mixture (C9–C30) in a wide range of chain-length, which could be potentially applied in enhancement of bioremediation.     

Virulence-associated genes and antibiotic susceptibility among vaginal and rectal <Emphasis Type="Italic">Escherichia coli</Emphasis> isolates from healthy pregnant women in Poland

Vaginal and/or rectal Escherichia coli colonization of pregnant women is sometimes associated with neonatal infections. Despite the relevance of these strains, they have been rarely described before. Thus, the aim of this study was to compare vaginal (VEC) and rectal E. coli (REC) isolates in respect of antimicrobial susceptibility and the frequency of virulence-associated genes (VAGs). The antimicrobial susceptibility of 50 VEC and 50 REC isolates was performed by using the disc diffusion method, and VAGs were detected by PCR. There were no significant differences in the antimicrobial resistance between VEC and REC. Both VEC and REC isolates were mostly resistant to ticarcillin (36 and 30%) and ampicillin (36 and 22%). None of the tested isolates was positive for ESBL. Gene’s fimH, fimA, sfa/foc, iutA, ibeA, hlyF, and neuC were detected, respectively, in 98, 92, 32, 28, 12, 8, and 2% of VEC and in 94, 72, 12, 34, 8, 10, and 8% of REC isolates. The co-occurrence of fimA/H and sfa/foc genes was significantly more prevalent among VEC isolates, in comparison to REC isolates. The study indicated that VEC and REC isolates are quite similar in terms of antimicrobial non-susceptibility and VAGs.     

Synthesis of functionalized benzo[<Emphasis Type="Italic">f</Emphasis>]2<Emphasis Type="Italic">H</Emphasis>-chromenes and evaluation of their antimicrobial activities

Knoevenagel cyclocondensations of α-hydroxy naphthaldehyde with β-oxodithioesters and ketene dithioacetals yielded 2H-benzo[f]chromene-2-thiones and 2H-benzo[f]chromen-2-ones, respectively, in high yields. The newly synthesized compounds were evaluated for antifungal and antibacterial activities. Among them, compounds (2-furyl)(3-thioxo-3H-benzo[f]chromen-2-yl)methanone and phenyl(3-oxo-3H-benzo[f]chromen-2-yl)methanone exhibited excellent antifungal activity against tested fungi Curvularia lunata and Fusarium moniliforme. The highest antibacterial activity against the tested bacteria Escherichia coli and Staphylococcus aureus was observed for (4-chlorophenyl)(3-oxo-3H-benzo[f]chromen-2-yl)methanone. The results of antimicrobial screening demonstrate that (2-furyl)(3-thioxo-3H-benzo[f]chromen-2-yl)methanone, phenyl(3-oxo-3H-benzo[f]chromen-2-yl)methanone, and (4-chlorophenyl)(3-oxo-3H-benzo[f]chromen-2-yl)methanone are promising as antimicrobial drugs.     

Korean indigenous bacterial species with valid names belonging to the phylum <Emphasis Type="Italic">Actinobacteria</Emphasis>

To understand the isolation and classification state of actinobacterial species with valid names for Korean indigenous isolates, isolation source, regional origin, and taxonomic affiliation of the isolates were studied. At the time of this writing, the phylum Actinobacteria consisted of only one class, Actinobacteria, including five subclasses, 10 orders, 56 families, and 330 genera. Moreover, new taxa of this phylum continue to be discovered. Korean actinobacterial species with a valid name has been reported from 1995 as Tsukamurella inchonensis isolated from a clinical specimen. In 1997, Streptomyces seoulensis was validated with the isolate from the natural Korean environment. Until Feb. 2016, 256 actinobacterial species with valid names originated from Korean territory were listed on LPSN. The species were affiliated with three subclasses (Acidimicrobidae, Actinobacteridae, and Rubrobacteridae), four orders (Acidimicrobiales, Actinomycetales, Bifidobacteriales, and Solirubrobacterales), 12 suborders, 36 families, and 93 genera. Most of the species belonged to the subclass Actinobacteridae, and almost of the members of this subclass were affiliated with the order Actinomycetales. A number of novel isolates belonged to the families Nocardioidaceae, Microbacteriaceae, Intrasporangiaceae, and Streptomycetaceae as well as the genera Nocardioides, Streptomyces, and Microbacterium. Twenty-six novel genera and one novel family, Motilibacteraceae, were created first with Korean indigenous isolates. Most of the Korean indigenous actionobacterial species were isolated from natural environments such as soil, seawater, tidal flat sediment, and fresh-water. A considerable number of species were isolated from artificial resources such as fermented foods, wastewater, compost, biofilm, and water-cooling systems or clinical specimens. Korean indigenous actinobacterial species were isolated from whole territory of Korea, and especially a large number of species were from Jeju, Gyeonggi, Jeonnam, Daejeon, and Chungnam. A large number of novel actinobacterial species continue to be discovered since the Korean government is encouraging the search for new bacterial species and researchers are endeavoring to find out novel strains from extreme or untapped environments.     

Characterization and antimicrobial activity of the bioactive metabolites in streptomycete isolates

Twenty different streptomycete isolates were obtained from soils of southeast Serbia. Five isolates identified as Streptomyces hygroscopicus (SH100, SH101, SH102, SH103, and SH104) showed strong activity against Botrytis cinerea, a parasite found in domestic vines. These isolates were extensively studied for their in vitro antimicrobial activity against Gram-positive bacteria, Gram-negative bacteria, yeasts and fungi, and also antiviral activity against Herpes simplex. The results indicated that the obtained isolates were highly active against Botrytis cinerea, Candida albicans, and Herpes simplex, with an inhibition zone at ≥31 mm. The structure of the bioactive components was determined using elemental analysis, as well as UV/VIS, FTIR, and TLC.     

Genomic characterisation,detection of genes encoding virulence factors and evaluation of antibiotic resistance of <Emphasis Type="Italic">Trueperella pyogenes</Emphasis> isolated from cattle with clinical metritis

Trueperella pyogenes is one of the most important microorganisms causing metritis in post-partum cattle. Co-infection with other bacterial species such as Escherichia coli or Fusobacterium necrofurom increases the severity of the disease and the persistence of bacteria in utero. The aim of this study was to investigate the frequency of T. pyogenes strains, and their virulence and antimicrobial resistant profiles in metritis cases. The study was carried out on 200 samples obtained from metritis discharges of postpartum cattle on 18 farms around Tehran, Iran. Sixty-five T. pyogenes isolates (32.5%) were identified, of which 16 isolates were detected as pure cultures and the other 49 isolates from cultures most commonly mixed with E. coli or F. necrofurom. In terms of diversity in biochemical characteristic of T. pyogenes strains, 8 different biotypes were identified among the isolates. Single or multi antimicrobial resistance was observed in 48 isolates (73.9%), which was mostly against trimethoprim sulfamethoxazole, azithromycin, erythromycin and streptomycin. The tetracycline resistance gene tetW and macrolide resistance genes ermB and ermX were detected in 30, 18 and 25 isolates, respectively. In the screening of genes encoding virulence factors, fimA and plo genes were identified in all tested isolates. Genes encoding nanP, nanH, fimC, fimG, fimE and cbpA were detected in 50, 54, 45, 40, 50 and 37 of isolates, respectively. Thirteen different genotypes were observed in these T. pyogenes isolates. A significant association between clonal types and virulence factor genes, biochemical profile, CAMP test result, severity of the disease and sampling time was detected.     

<Emphasis Type="Italic">Aeromonas</Emphasis> and <Emphasis Type="Italic">Plesiomonas</Emphasis> species from scarlet ibis (<Emphasis Type="Italic">Eudocimus ruber</Emphasis>) and their environment: monitoring antimicrobial susceptibility and virulence

The present study aimed at evaluating the role of captive scarlet ibises (Eudocimus ruber) and their environment as reservoirs of Aeromonas spp. and Plesiomonas spp., and analyzing the in vitro antimicrobial susceptibility and virulence of the recovered bacterial isolates. Thus, non-lactose and weak-lactose fermenting, oxidase positive Gram-negative bacilli were recovered from cloacal samples (n = 30) of scarlet ibises kept in a conservational facility and from water samples (n = 30) from their environment. Then, the antimicrobial susceptibility, hemolytic activity and biofilm production of the recovered Aeromonas spp. and Plesiomonas shigelloides strains were assessed. In addition, the virulence-associated genes of Aeromonas spp. were detected. Ten Aeromonas veronii bv. sobria, 2 Aeromonas hydrophila complex and 10 P. shigelloides were recovered. Intermediate susceptibility to piperacillin-tazobactam and cefepime was observed in 2 Aeromonas spp. and 1 P. shigelloides, respectively, and resistance to gentamicin was observed in 4 P. shigelloides. The automated susceptibility analysis revealed resistance to piperacillin-tazobactam and meropenem among Aeromonas spp. and intermediate susceptibility to gentamicin among P. shigelloides. All Aeromonas isolates presented hemolytic activity, while 3 P. shigelloides were non-hemolytic. All Aeromonas spp. and 3/10 P. shigelloides were biofilm-producers, at 28 °C, while 10 Aeromonas spp. and 6/10 P. shigelloides produced biofilms, at 37 °C. The most prevalent virulence genes of Aeromonas spp. were asa1 and ascV. Scarlet ibises and their environment harbour potentially pathogenic bacteria, thus requiring monitoring and measures to prevent contamination of humans and other animals.     

The bacterial diversity in a Brazilian non-disturbed mangrove sediment

The bacterial diversity present in sediments of a well-preserved mangrove in Ilha do Cardoso, located in the extreme south of São Paulo State coastline, Brazil, was assessed using culture-independent molecular approaches (denaturing gradient gel electrophoresis (DGGE) and analysis of 166 sequences from a clone library). The data revealed a bacterial community dominated by Alphaproteobacteria (40.36% of clones), Gammaproteobacteria (19.28% of clones) and Acidobacteria (27.71% of clones), while minor components of the assemblage were affiliated to Betaproteobacteria, Deltaproteobacteria, Firmicutes, Actinobacteria and Bacteroidetes. The clustering and redundancy analysis (RDA) based on DGGE were used to determine factors that modulate the diversity of bacterial communities in mangroves, such as depth, seasonal fluctuations, and locations over a transect area from the sea to the land. Profiles of specific DGGE gels showed that both dominant (‘universal’ Bacteria and Alphaproteobacteria) and low-density bacterial communities (Betaproteobacteria and Actinobacteria) are responsive to shifts in environmental factors. The location within the mangrove was determinant for all fractions of the community studied, whereas season was significant for Bacteria, Alphaproteobacteria, and Betaproteobacteria and sample depth determined the diversity of Alphaproteobacteria and Actinobacteria.     

Possible Probiotic Lactic Acid Bacteria Isolated from Oysters (<Emphasis Type="Italic">Crassostrea gigas</Emphasis>)

We attempted to isolate lactic acid bacteria (LAB) from the marine oyster (Crassostrea gigas) and selected several environmental stress-resistant isolates for the development of a future probiotic adjuvant for marine aquaculture. Twenty-six presumptive LAB isolates were extracted from oysters and screened (by an agar diffusion assay) for antimicrobial activity toward various pathogens: Vibrio parahaemolyticus, Streptococcus iniae, and Edwardsiella tarda. Eight isolates had an antibacterial activity toward V. parahaemolyticus; in particular, 6 isolates showed a growth-inhibitory activity, with inhibition zone diameters > 15 mm. Of these, 5 isolates (JL17, JL18, JL28, HL7, and HL32) were also active against S. iniae and E. tarda. Enterococcus faecium HL7 was selected as the isolate most resistant to environmental stressors: the minimum NaCl, ethanol, and hydrogen peroxide concentrations at which HL7 cells lost their viability were 1.9 M, 11%, and 0.013%, respectively. When an antibiotic sensitivity test was performed on E. faecium HL7, this isolate was found to be resistant to trimethoprim/sulfamethoxazole, cephalothin, ampicillin, rifampin, gentamicin, cefotaxime, cefepime, cefotetan, nalidixic acid, and kanamycin. While the oyster model studies provided indication that E. faecium HL7 could be a good candidate as biocontrol agent against V. vulnificus, further optimization is needed in the actual animal rearing situation.     

5-Nitroimidazole-derived Schiff bases and their copper(II) complexes exhibit potent antimicrobial activity against pathogenic anaerobic bacteria

In the present work a family of novel secnidazole-derived Schiff base compounds and their copper(II) complexes were synthesized. The antimicrobial activities of the compounds were evaluated against clinically important anaerobic bacterial strains. The compounds exhibited in vitro antibacterial activity against Bacteroides fragilis, Bacteroides thetaiotaomicron, Bacteroides vulgatus, Bacteroides ovatus, Parabacteroides distasonis and Fusubacterium nucleatum pathogenic anaerobic bacteria. Upon coordination to copper(II) the antibacterial activity significantly increased in several cases. Some derivatives were even more active than the antimicrobial drugs secnidazole and metronidazole. Therefore, the compounds under study are suitable for in vivo evaluation and the microorganisms should be classified as susceptible to them. Electrochemical studies on the reduction of the nitro group revealed that the compounds show comparable reduction potentials, which are in the same range of the bio-reducible drugs secnidazole and benznidazole. The nitro group reduction potential is more favorable for the copper(II) complexes than for the starting ligands. Hence, the antimicrobial activities of the compounds under study might in part be related to intracellular bio-reduction activation. Considering the increasing resistance rates of anaerobic bacteria against a wide range of antimicrobial drugs, the present work constitutes an important contribution to the development of new antibacterial drug candidates.     

Bacterial diversity obtained by culturable approaches in the gut of <Emphasis Type="Italic">Glossina pallidipes</Emphasis> population from a non sleeping sickness focus in Tanzania: preliminary results

Background

Glossina pallidipes is a haematophagous insect that serves as a cyclic transmitter of trypanosomes causing African Trypanosomiasis (AT). To fully assess the role of G. pallidipes in the epidemiology of AT, especially the human form of the disease (HAT), it is essential to know the microbial diversity inhabiting the gut of natural fly populations. This study aimed to examine the diversity of G. pallidipes fly gut bacteria by culture-dependent approaches.

Results

113 bacterial isolates were obtained from aerobic and anaerobic microorganisms originating from the gut of G. pallidipes. 16S rDNA of each isolate was PCR amplified and sequenced. The overall majority of identified bacteria belonged in descending order to the Firmicutes (86.6%), Actinobacteria (7.6%), Proteobacteria (5.5%)and Bacteroidetes (0.3%). Diversity of Firmicutes was found higher when enrichments and isolation were performed under anaerobic conditions than aerobic ones. Experiments conducted in the absence of oxygen (anaerobiosis) led to the isolation of bacteria pertaining to four phyla (83% Firmicutes, 15% Actinobacteria, 1% Proteobacteria and 0.5% Bacteroidetes, whereas those conducted in the presence of oxygen (aerobiosis) led to the isolation of bacteria affiliated to two phyla only (90% Firmicutes and 10% Proteobacteria). Phylogenetic analyses placed these isolates into 11 genera namely Bacillus, Acinetobacter, Mesorhizobium, Paracoccus, Microbacterium, Micrococcus, Arthrobacter, Corynobacterium, Curtobacterium, Vagococcus and Dietzia spp.which are known to be either facultative anaerobes, aerobes, or even microaerobes.

Conclusion

This study shows that G. pallidipes fly gut is an environmental reservoir for a vast number of bacterial species, which are likely to be important for ecological microbial well being of the fly and possibly on differing vectorial competence and refractoriness against AT epidemiology.

     

Diversity and dynamics of the bacterial community involved in pig manure biodegradation in a microbial fermentation bed system

Overproduction of livestock manures with unpleasant odors causes significant environmental problems. The microbial fermentation bed (MFB) system is considered an effective approach to recycling utilization of agricultural byproducts and pig manure (PM). To gain a better understanding of bacterial communities present during the degradation of PM in MFB, the PM bacterial community was evaluated at different fermentation stages using 16S rRNA high throughput sequencing technology. The heatmap plot clustered five samples into short-term fermentation stage of 0–10 days and long-term fermentation stage of 15–20 days. The most abundant OTUs at the phylum level were Firmicutes, Actinobacteria and Proteobacteria in the long-term fermentation stage of PM, whereas Firmicutes, Bacteroidetes, and Proteobacteria predominated in the short-term fermentation stage of PM. At the genus level, organic degradation strains, such as Corynebacterium, Bacillus, Virgibacillus, Pseudomonas, Actinobacteria, Lactobacillus, Pediococcus were the predominate genera at the long-term fermentation stage, but were found only rarely in the short-term fermentation stage. C/N ratios increased and the concentration of the unpleasant odor substance 3-hydroxy-5-methylisoxazole (3-MI) decreased with prolonged period of fermentation. Redundancy analysis (RDA) demonstrated that the relative abundance of Firmicutes, Actinobacteria, Acidobacteria and Proteobacteria had a close relationship with degradation of 3-MI and increasing C/N ratio. These results provide valuable additional information about bacterial community composition during PM biodegradation in animal husbandry.     

Drug resistance mutations and susceptibility phenotypes of <Emphasis Type="Italic">Neisseria gonorrhoeae</Emphasis> isolates in Russia

Steady growth in the degree of antimicrobial resistance in Neisseria gonorrhoeae calls for the control of the spreading of resistance mutations. Here we present the data describing drug resistance mutations, the results of antimicrobial susceptibility tests, and molecular genotypes of 128 recent N. gonorrhoeae isolates collected across 9 regions of the Russian Federation. The mutations in chromosome genes penA, ponA, rpsJ, gyrA, parC, which determine the susceptibility of N. gonorrhoeae to penicillins, tetracyclines, and fluoroquinolones were detected by multiplex amplification followed by hybridization on a hydrogel microarray. The most frequent mutation was an insertion of an aspartate at position 345 of penA gene (76.6%), whereas mutations Leu421Pro in ponA gene, Val57Met in rpsJ gene, Ser91Phe in gyrA gene, Asp95Gly in gyrA gene, and Ser87Arg in parC gene were detected in 32.8–36.7% of strains. One third of studied N. gonorrhoeae isolates harbored multiple drug resistance mutations in bacterial chromosome, resulting in the bimodal distribution of mutation profiles and related patterns of antimicrobial susceptibility. The spread of multiple resistance could be explained by the vertical transfer of the mutations resulting in the clonality of the N. gonorrhoeae population.