BACKGROUND: Many arthropods rely on their gut microbiome to digest plant material, which is often low in nitrogen but high in complex polysaccharides. Detritivores, such as millipedes, live on a particularly poor diet, but the identity and nutritional contribution of their microbiome are largely unknown. In this study, the hindgut microbiota of the tropical millipede Epibolus pulchripes (large, methane emitting) and the temperate millipede Glomeris connexa (small, non-methane emitting), fed on an identical diet, were studied using comparative metagenomics and metatranscriptomics. RESULTS: The results showed that the microbial load in E. pulchripes is much higher and more diverse than in G. connexa. The microbial communities of the two species differed significantly, with Bacteroidota dominating the hindguts of E. pulchripes and Proteobacteria (Pseudomonadota) in G. connexa. Despite equal sequencing effort, de novo assembly and binning recovered 282 metagenome-assembled genomes (MAGs) from E. pulchripes and 33 from G. connexa, including 90 novel bacterial taxa (81 in E. pulchripes and 9 in G. connexa). However, despite this taxonomic divergence, most of the functions, including carbohydrate hydrolysis, sulfate reduction, and nitrogen cycling, were common to the two species. Members of the Bacteroidota (Bacteroidetes) were the primary agents of complex carbon degradation in E. pulchripes, while members of Proteobacteria dominated in G. connexa. Members of Desulfobacterota were the potential sulfate-reducing bacteria in E. pulchripes. The capacity for dissimilatory nitrate reduction was found in Actinobacteriota (E. pulchripes) and Proteobacteria (both species), but only Proteobacteria possessed the capacity for denitrification (both species). In contrast, some functions were only found in E. pulchripes. These include reductive acetogenesis, found in members of Desulfobacterota and Firmicutes (Bacillota) in E. pulchripes. Also, diazotrophs were only found in E. pulchripes, with a few members of the Firmicutes and Proteobacteria expressing the nifH gene. Interestingly, fungal-cell-wall-degrading glycoside hydrolases (GHs) were among the most abundant carbohydrate-active enzymes (CAZymes) expressed in both millipede species, suggesting that fungal biomass plays an important role in the millipede diet. CONCLUSIONS: Overall, these results provide detailed insights into the genomic capabilities of the microbial community in the hindgut of millipedes and shed light on the ecophysiology of these essential detritivores. Video Abstract.

• Klíčová slova
• Acetogens, Ecosystem engineers, Glycoside hydrolases, Hindgut microbiota, Millipede holobiont, Nutrient cycling, Polysaccharide degradation, Symbiosis,
• MeSH
• Bacteria MeSH
• Bacteroidetes genetika   MeSH
• členovci * genetika   MeSH
• dusík metabolismus   MeSH
• fylogeneze MeSH
• metagenom MeSH
• metagenomika MeSH
• Proteobacteria genetika   MeSH
• sacharidy MeSH
• sírany metabolismus   MeSH
• střevní mikroflóra * genetika   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• audiovizuální média MeSH
• časopisecké články MeSH
• Názvy látek
• dusík MeSH
• sacharidy MeSH
• sírany MeSH

Biofilm is a complex community of microorganisms residing within a polysaccharide and/or protein matrix. Biofilm can be produced by several microorganisms, including various bacteria and fungi. Nowadays, the resistance of biofilm-growing cells to antimicrobials originated from the structural nature of biofilms, and phenotypic alteration of sessile cells is becoming a global issue. Bacterial biofilms are important in various aspects of human health, including chronic infections, dental plaque, and infection of indwelling medical devices such as catheters. They are also a major problem in other industries, including oil recovery, drinking water distribution, papermaking, metalworking, and food processing. Estimates indicate that more than 80% of infectious diseases are biofilm-derived. The aim of this study is to describe mechanisms of antibiotic resistance to provide a better perspective on how to manage it. Moreover, the current strategies for biofilm inhibition were described. Considering that plants are a valuable source of abundant natural chemicals to create prophylactic and therapeutic medicines against biofilm-based infections, significant natural compounds with anti-biofilm properties were highlighted. Finally, natural anti-biofilm compounds under clinical trial evaluation were summarized to provide a background for more extensive researches and assist in opening a new window to novel treatments.

• MeSH
• antibakteriální látky farmakologie   MeSH
• antiinfekční látky * MeSH
• Bacteria MeSH
• biofilmy * MeSH
• houby MeSH
• lidé MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• antibakteriální látky MeSH
• antiinfekční látky * MeSH

Commensal bacterium Clostridium paraputrificum J4 produces several extracellular chitinolytic enzymes including a 62 kDa chitinase Chit62J4 active toward 4-nitrophenyl N,N'-diacetyl-β-d-chitobioside (pNGG). We characterized the crude enzyme from bacterial culture fluid, recombinant enzyme rChit62J4, and its catalytic domain rChit62J4cat. This major chitinase, securing nutrition of the bacterium in the human intestinal tract when supplied with chitin, has a pH optimum of 5.5 and processes pNGG with Km = 0.24 mM and kcat = 30.0 s-1. Sequence comparison of the amino acid sequence of Chit62J4, determined during bacterial genome sequencing, characterizes the enzyme as a family 18 glycosyl hydrolase with a four-domain structure. The catalytic domain has the typical TIM barrel structure and the accessory domains-2x Fn3/Big3 and a carbohydrate binding module-that likely supports enzyme activity on chitin fibers. The catalytic domain is highly homologous to a single-domain chitinase of Bacillus cereus NCTU2. However, the catalytic profiles significantly differ between the two enzymes despite almost identical catalytic sites. The shift of pI and pH optimum of the commensal enzyme toward acidic values compared to the soil bacterium is the likely environmental adaptation that provides C. paraputrificum J4 a competitive advantage over other commensal bacteria.

• Klíčová slova
• adaptation to the environment, chitinase, exochitinase, glycosyl hydrolase family 18, human commensal bacterium,
• MeSH
• bakteriální proteiny genetika   metabolismus   MeSH
• chitin metabolismus   MeSH
• chitinasy chemie   genetika   metabolismus   MeSH
• Clostridium růst a vývoj   izolace a purifikace   metabolismus   MeSH
• katalytická doména MeSH
• koncentrace vodíkových iontů MeSH
• lidé MeSH
• rekombinantní proteiny genetika   metabolismus   MeSH
• střevní mikroflóra MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• bakteriální proteiny MeSH
• chitin MeSH
• chitinasy MeSH
• rekombinantní proteiny MeSH

The mammalian gastrointestinal (GI) microbiome, which plays indispensable roles in host nutrition and health, is affected by numerous intrinsic and extrinsic factors. Among them, antibiotic (ATB) treatment is reported to have a significant effect on GI microbiome composition in humans and other animals. However, the impact of ATBs on the GI microbiome of free-ranging or even captive great apes remains poorly characterized. Here, we investigated the effect of cephalosporin treatment (delivered by intramuscular dart injection during a serious respiratory outbreak) on the GI microbiome of a wild habituated group of western lowland gorillas (Gorilla gorilla gorilla) in the Dzanga Sangha Protected Areas, Central African Republic. We examined 36 fecal samples from eight individuals, including samples before and after ATB treatment, and characterized the GI microbiome composition using Illumina-MiSeq sequencing of the bacterial 16S rRNA gene. The GI microbial profiles of samples from the same individuals before and after ATB administration indicate that the ATB treatment impacts GI microbiome stability and the relative abundance of particular bacterial taxa within the colonic ecosystem of wild gorillas. We observed a statistically significant increase in Firmicutes and a decrease in Bacteroidetes levels after ATB treatment. We found disruption of the fibrolytic community linked with a decrease of Ruminoccocus levels as a result of ATB treatment. Nevertheless, the nature of the changes observed after ATB treatment differs among gorillas and thus is dependent on the individual host. This study has important implications for ecology, management, and conservation of wild primates.

• Klíčová slova
• Antibiotics, Bacteria, Gastrointestinal microbiome, Gorilla, Illumina MiSeq, Medical treatment,
• MeSH
• antibakteriální látky farmakologie   MeSH
• Bacteroidetes růst a vývoj   MeSH
• cefalosporiny farmakologie   MeSH
• feces mikrobiologie   MeSH
• Firmicutes růst a vývoj   MeSH
• Gorilla gorilla mikrobiologie   MeSH
• nemoci lidoopů farmakoterapie   MeSH
• RNA ribozomální 16S genetika   MeSH
• Ruminococcus růst a vývoj   MeSH
• střevní mikroflóra účinky léků   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Geografické názvy
• Středoafrická republika MeSH
• Názvy látek
• antibakteriální látky MeSH
• cefalosporiny MeSH
• RNA ribozomální 16S MeSH

Although the critical role that our gastrointestinal microbes play in host physiology is now well established, we know little about the factors that influenced the evolution of primate gut microbiomes. To further understand current gut microbiome configurations and diet-microbe co-metabolic fingerprints in primates, from an evolutionary perspective, we characterized fecal bacterial communities and metabolomic profiles in 228 fecal samples of lowland and mountain gorillas (G. g. gorilla and G. b. beringei, respectively), our closest evolutionary relatives after chimpanzees. Our results demonstrate that the gut microbiomes and metabolomes of these two species exhibit significantly different patterns. This is supported by increased abundance of metabolites and bacterial taxa associated with fiber metabolism in mountain gorillas, and enrichment of markers associated with simple sugar, lipid and sterol turnover in the lowland species. However, longitudinal sampling shows that both species' microbiomes and metabolomes converge when hosts face similar dietary constraints, associated with low fruit availability in their habitats. By showing differences and convergence of diet-microbe co-metabolic fingerprints in two geographically isolated primate species, under specific dietary stimuli, we suggest that dietary constraints triggered during their adaptive radiation were potential factors behind the species-specific microbiome patterns observed in primates today.

• MeSH
• Bacteria klasifikace   genetika   izolace a purifikace   MeSH
• biologická evoluce MeSH
• druhová specificita MeSH
• feces mikrobiologie   MeSH
• gastrointestinální trakt metabolismus   mikrobiologie   MeSH
• Gorilla gorilla metabolismus   mikrobiologie   MeSH
• krmivo pro zvířata analýza   MeSH
• potravní vláknina metabolismus   MeSH
• střevní mikroflóra * MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The expression of Ruminococcus flavefaciens 007S cellulases in different incubation time points (growth stages) and their substrate inducibility were analyzed by comparing the zymogram expression profiles of cultures grown on insoluble cellulose (Avicel) with cellobiose-grown cultures. The molecular weights of the enzymes were compared to (putative) cellulases encoded in the R. flavefaciens FD-1 genome.

• MeSH
• bakteriální proteiny chemie   genetika   metabolismus   MeSH
• celobiosa metabolismus   MeSH
• celulasy chemie   genetika   metabolismus   MeSH
• celulosa metabolismus   MeSH
• enzymatické testy MeSH
• exprese genu MeSH
• molekulární sekvence - údaje MeSH
• molekulová hmotnost MeSH
• Ruminococcus chemie   enzymologie   genetika   růst a vývoj   MeSH
• terciární struktura proteinů MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• bakteriální proteiny MeSH
• celobiosa MeSH
• celulasy MeSH
• celulosa MeSH