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Biological Research May 2022The study of the stress responses in bacteria has given us a wealth of information regarding the mechanisms employed by these bacteria in aggressive or even non-optimal... (Review)
Review
The study of the stress responses in bacteria has given us a wealth of information regarding the mechanisms employed by these bacteria in aggressive or even non-optimal living conditions. This information has been applied by several researchers to identify molecular targets related to pathogeny, virulence, and survival, among others, and to design new prophylactic or therapeutic strategies against them. In this study, our knowledge of these mechanisms has been summarized with emphasis on some aquatic pathogenic bacteria of relevance to the health and productive aspects of Chilean salmon farming (Piscirickettsia salmonis, Tenacibaculum spp., Renibacterium salmoninarum, and Yersinia ruckeri). This study will aid further investigations aimed at shedding more light on possible lines of action for these pathogens in the coming years.
Topics: Aquaculture; Chile; Micrococcaceae; Virulence Factors
PubMed: 35642071
DOI: 10.1186/s40659-022-00391-5 -
Frontiers in Cellular and Infection... 2021The oral microbiota has been observed to be influenced by cigarette smoking and linked to several human diseases. However, research on the effect of cigarette smoking on...
The oral microbiota has been observed to be influenced by cigarette smoking and linked to several human diseases. However, research on the effect of cigarette smoking on the oral microbiota has not been systematically conducted in the Chinese population. We profiled the oral microbiota of 316 healthy subjects in the Chinese population by 16S rRNA gene sequencing. The alpha diversity of oral microbiota was different between never smokers and smokers ( = 0.002). Several bacterial taxa were first reported to be associated with cigarette smoking by LEfSe analysis, including ( = 1.56E-04), ( = 1.65E-06), and ( = 3.52E-02) at the genus level and ( = 1.55E-02), ( = 8.48E-08), ( = 4.13E-03), ( = 1.79E-06), ( = 3.83E-06), ( = 2.28E-04), and ( = 4.82E-02) at the species level. Two nitrite-producing bacteria that can increase the acidity of the oral cavity, and , were also enriched in smokers with FDR-adjusted -values of 3.62E-06 and 1.10E-06, respectively. Notably, we observed that two acid production-related pathways, amino acid-related enzymes ( = 6.19E-05) and amino sugar and nucleotide sugar metabolism ( = 2.63E-06), were increased in smokers by PICRUSt analysis. Finally, the co-occurrence analysis demonstrated that smoker-enriched bacteria were significantly positively associated with each other and were negatively correlated with the bacteria decreased in smokers. Our results suggested that cigarette smoking may affect oral health by creating a different environment by altering bacterial abundance, connections among oral microbiota, and the microbiota and their metabolic function.
Topics: China; Cigarette Smoking; Humans; Microbiota; Micrococcaceae; Prevotella; RNA, Ribosomal, 16S
PubMed: 34123872
DOI: 10.3389/fcimb.2021.658203 -
Nature Medicine Apr 2020Mucosal immunity develops in the human fetal intestine by 11-14 weeks of gestation, yet whether viable microbes exist in utero and interact with the intestinal immune...
Mucosal immunity develops in the human fetal intestine by 11-14 weeks of gestation, yet whether viable microbes exist in utero and interact with the intestinal immune system is unknown. Bacteria-like morphology was identified in pockets of human fetal meconium at mid-gestation by scanning electron microscopy (n = 4), and a sparse bacterial signal was detected by 16S rRNA sequencing (n = 40 of 50) compared to environmental controls (n = 87). Eighteen taxa were enriched in fetal meconium, with Micrococcaceae (n = 9) and Lactobacillus (n = 6) the most abundant. Fetal intestines dominated by Micrococcaceae exhibited distinct patterns of T cell composition and epithelial transcription. Fetal Micrococcus luteus, isolated only in the presence of monocytes, grew on placental hormones, remained viable within antigen presenting cells, limited inflammation ex vivo and possessed genomic features linked with survival in the fetus. Thus, viable bacteria are highly limited in the fetal intestine at mid-gestation, although strains with immunomodulatory capacity are detected in subsets of specimens.
Topics: Autopsy; Bacteria; Bacterial Typing Techniques; Female; Fetus; Gastrointestinal Microbiome; Gestational Age; Humans; Infant, Newborn; Intestinal Mucosa; Intestines; Lactobacillus; Meconium; Microbial Viability; Micrococcaceae; Pregnancy; Pregnancy Trimester, Second; RNA, Ribosomal, 16S
PubMed: 32094926
DOI: 10.1038/s41591-020-0761-3 -
Frontiers in Cellular and Infection... 2021Oral microbiota is constantly changing with the host state, whereas the oral microbiome of chronic erythematous candidiasis remains poorly understood. The aim of this...
Oral microbiota is constantly changing with the host state, whereas the oral microbiome of chronic erythematous candidiasis remains poorly understood. The aim of this study was to compare oral microbial signatures and functional profiling between chronic erythematous candidiasis and healthy subjects. Using shotgun metagenomic sequencing, we analyzed the microbiome in 12 chronic erythematous candidiasis, 12 healthy subjects, and 2 chronic erythematous candidiasis cured by antifungal therapy. We found that the salivary microbiota of chronic erythematous candidiasis was significantly different from that of healthy subjects. Among them, and were the most abundant disease-enriched species (Mann-Whitney U-test, < 0.05). In addition, co-occurrence network analysis showed that formed densely connected modules with oral bacterial species and was mainly positive connected to species. Furthermore, we investigated the functional potentials of the microbiome and identified a set of microbial marker genes associated with chronic erythematous candidiasis. Some of these genes enriching in chronic erythematous candidiasis are involved in eukaryotic ribosome, putative glutamine transport system, and cytochrome bc1 complex respiratory unit. Altogether, this study revealed the changes of oral microbial composition, the co-occurrence between and oral bacteria, as well as the changes of microbial marker genes during chronic erythematous candidiasis, which provides evidence of oral microbiome as a target for the treatment and prevention of chronic erythematous candidiasis.
Topics: Candidiasis, Oral; Humans; Metagenomics; Microbiota; Micrococcaceae
PubMed: 34490138
DOI: 10.3389/fcimb.2021.691092 -
Journal of Bacteriology Jul 2017Dormancy is a protective state in which diverse bacteria, including , , (syphilis), and (Lyme disease), curtail metabolic activity to survive external stresses,...
Dormancy is a protective state in which diverse bacteria, including , , (syphilis), and (Lyme disease), curtail metabolic activity to survive external stresses, including antibiotics. Evidence suggests dormancy consists of a continuum of interrelated states, including viable but nonculturable (VBNC) and persistence states. VBNC and persistence contribute to antibiotic tolerance, reemergence from latent infections, and even quorum sensing and biofilm formation. Previous studies indicate that the protein mechanisms regulating persistence and VBNC states are not well understood. We have queried the VBNC state of NCTC 2665 (MI-2665) by quantitative proteomics combining gel electrophoresis, high-performance liquid chromatography, and tandem mass spectrometry to elucidate some of these mechanisms. MI-2665 is a nonpathogenic actinobacterium containing a small (2.5-Mb), high-GC-content genome which exhibits a well-defined VBNC state induced by nutrient deprivation. The MI-2665 VBNC state demonstrated a loss of protein diversity accompanied by increased levels of 18 proteins that are conserved across actinobacteria, 14 of which have not been previously identified in VNBC. These proteins implicate an anaplerotic strategy in the transition to VBNC, including changes in the glyoxylate shunt, redox and amino acid metabolism, and ribosomal regulatory processes. Our data suggest that MI-2665 is a viable model for dissecting the protein mechanisms underlying the VBNC stress response and provide the first protein-level signature of this state. We expect that this protein signature will enable future studies deciphering the protein mechanisms of dormancy and identify novel therapeutic strategies effective against antibiotic-tolerant bacterial infections. Dormancy is a protective state enabling bacteria to survive antibiotics, starvation, and the immune system. Dormancy is comprised of different states, including persistent and viable but nonculturable (VBNC) states that contribute to the spread of bacterial infections. Therefore, it is imperative to identify how bacteria utilize these different dormancy states to survive antibiotic treatment. The objective of our research is to eliminate dormancy as a route to antibiotic tolerance by understanding the proteins that control dormancy in NCTC 2665. This bacterium has unique advantages for studying dormancy, including a small genome and a well-defined and reproducible VBNC state. Our experiments implicate four previously identified and 14 novel proteins upregulated in VBNC that may regulate this critical survival mechanism.
Topics: Bacterial Proteins; Bacteriological Techniques; Gene Expression Regulation, Bacterial; Micrococcus luteus; Proteomics; Stress, Physiological
PubMed: 28484042
DOI: 10.1128/JB.00206-17 -
The ISME Journal Jan 2024The widespread occurrence of sulfonamides raises significant concerns about the evolution and spread of antibiotic resistance genes. Biodegradation represents not only a...
The widespread occurrence of sulfonamides raises significant concerns about the evolution and spread of antibiotic resistance genes. Biodegradation represents not only a resistance mechanism but also a clean-up strategy. Meanwhile, dynamic and diverse environments could influence the cellular function of individual sulfonamide-degrading strains. Here, we present Paenarthrobacter from different origins that demonstrated diverse growth patterns and sulfonamide-degrading abilities. Generally, the degradation performance was largely associated with the number of sadA gene copies and also relied on its genotype. Based on the survey of sad genes in the public database, an independent mobilization of transposon-borne genes between chromosome and plasmid was observed. Insertions of multiple sadA genes could greatly enhance sulfonamide-degrading performance. Moreover, the sad gene cluster and sadA transposable element showed phylogenetic conservation currently, being identified only in two genera of Paenarthrobacter (Micrococcaceae) and Microbacterium (Microbacteriaceae). Meanwhile, Paenarthrobacter exhibited a high capacity for genome editing to adapt to the specific environmental niche, opening up new opportunities for bioremediation applications.
Topics: Sulfonamides; Biodegradation, Environmental; Phylogeny; Sulfanilamide; Micrococcaceae
PubMed: 38366247
DOI: 10.1093/ismejo/wrad040 -
CRISPR arrays as high-resolution markers to track microbial transmission during influenza infection.Microbiome Jun 2023Disruption of the microbial community in the respiratory tract due to infections, like influenza, could impact transmission of bacterial pathogens. Using samples from a...
BACKGROUND
Disruption of the microbial community in the respiratory tract due to infections, like influenza, could impact transmission of bacterial pathogens. Using samples from a household study, we determined whether metagenomic-type analyses of the microbiome provide the resolution necessary to track transmission of airway bacteria. Microbiome studies have shown that the microbial community across various body sites tends to be more similar between individuals who cohabit in the same household than between individuals from different households. We tested whether there was increased sharing of bacteria from the airways within households with influenza infections as compared to control households with no influenza.
RESULTS
We obtained 221 respiratory samples that were collected from 54 individuals at 4 to 5 time points across 10 households, with and without influenza infection, in Managua, Nicaragua. From these samples, we generated metagenomic (whole genome shotgun sequencing) datasets to profile microbial taxonomy. Overall, specific bacteria and phages were differentially abundant between influenza positive households and control (no influenza infection) households, with bacteria like Rothia, and phages like Staphylococcus P68virus that were significantly enriched in the influenza-positive households. We identified CRISPR spacers detected in the metagenomic sequence reads and used these to track bacteria transmission within and across households. We observed a clear sharing of bacterial commensals and pathobionts, such as Rothia, Neisseria, and Prevotella, within and between households. However, due to the relatively small number of households in our study, we could not determine if there was a correlation between increased bacterial transmission and influenza infection.
CONCLUSION
We observed that airway microbial composition differences across households were associated with what appeared to be different susceptibility to influenza infection. We also demonstrate that CRISPR spacers from the whole microbial community can be used as markers to study bacterial transmission between individuals. Although additional evidence is needed to study transmission of specific bacterial strains, we observed sharing of respiratory commensals and pathobionts within and across households. Video Abstract.
Topics: Humans; Clustered Regularly Interspaced Short Palindromic Repeats; Influenza, Human; Bacteria; Metagenome; Microbiota; Micrococcaceae
PubMed: 37330554
DOI: 10.1186/s40168-023-01568-0 -
Marine Drugs Oct 2021Four new chlorinated meroterpenoids, merochlorins G-J (-), and , a dihydronaphthalenedione precursor, along with known merochlorins A () and C-F (-), were obtained from...
Four new chlorinated meroterpenoids, merochlorins G-J (-), and , a dihydronaphthalenedione precursor, along with known merochlorins A () and C-F (-), were obtained from cultivation of the bacterium strain sp. CNH-189, which was isolated from marine sediment. The planar structures of compounds - and were elucidated by interpretation of MS, UV, and NMR spectroscopic data. The relative configurations of compounds - were determined via analysis of nuclear Overhauser effect (NOE) spectroscopic data, after which their absolute configurations were established by comparing the experimental electronic circular dichroism (ECD) spectra of compounds - to those of previously reported possible enantiomer models and DP4 calculations. Compound displayed strong antibacterial activities against , , and , with MIC values of 1, 2, and 2 μg/mL, respectively, whereas compound exhibited weak antibacterial effects on these three strains, with a 16-32 μg/mL MIC value range.
Topics: Animals; Anti-Bacterial Agents; Aquatic Organisms; Bacillus subtilis; Microbial Sensitivity Tests; Micrococcaceae; Staphylococcus aureus; Streptomyces; Terpenes
PubMed: 34822489
DOI: 10.3390/md19110618 -
Journal of the Pediatric Infectious... Apr 2021We performed a retrospective study to determine the epidemiology of Rothia mucilaginosa infections among pediatric cancer patients. Over 20 years, 37 cases were...
We performed a retrospective study to determine the epidemiology of Rothia mucilaginosa infections among pediatric cancer patients. Over 20 years, 37 cases were identified; 27% developed complications, but there was no infection-related mortality. All cases were successfully treated with vancomycin.
Topics: Bacteremia; Child; Humans; Micrococcaceae; Neoplasms; Retrospective Studies
PubMed: 32448911
DOI: 10.1093/jpids/piaa047 -
Frontiers in Cellular and Infection... 2020While extensive literature exists about the role of oral bacterial pathogens like and in oral squamous cell carcinoma (OSCC), the role of health-associated species has...
While extensive literature exists about the role of oral bacterial pathogens like and in oral squamous cell carcinoma (OSCC), the role of health-associated species has been largely unexplored. In this study, we assessed the effect of , and on proliferation and expression of marker genes (IL-6, TNF-α, MMP3, CD36, CCD1, and NANOG) in OSCC cell lines CAL27, SCC25, and SCC4. was included as a pathogenic control. Both bacterial lysates (3 concentrations) and live cells (3 MOIs) were tested. , and resulted in substantial, dose-dependent reduction of proliferation, which was found to be mediated by HO for the former and intracellular infection in the latter two species. However, only showed differential antiproliferative effect against the cancer cell lines vs. the normal control (TIGKs). In the gene expression assays, the health-associated species mostly downregulated CD36, a gene that plays an important role in tumor growth and metastasis, while upregulated it. IL6 and TNF expression, on the other hand, was upregulated by almost all species, particularly the Gram-negatives including . The effect on other genes was less evident and varied significantly by cell line. This exploratory study is the first insight into how health-associated bacteria may interact with OSCC. Further studies to explore whether the observed effects may have implications for the prevention or treatment of oral cancer are warranted.
Topics: Burkholderiaceae; Carcinoma, Squamous Cell; Fusobacterium nucleatum; Humans; Hydrogen Peroxide; Micrococcaceae; Mouth Neoplasms; Neisseria; Porphyromonas gingivalis; Veillonella
PubMed: 33123499
DOI: 10.3389/fcimb.2020.575656