Transition of the genital mollicutes from the second to the third trimester of pregnancy and its association with adverse pregnancy outcomes in GDM women: a prospective, single-center cohort study from China.

BACKGROUND: The association of genital Mollicutes infection transition with adverse pregnancy outcomes was insignificant among general pregnant women, but there remains a paucity of evidence linking this relationship in gestational diabetes mellitus (GDM) women. The aim was to investigate the association between genital Mollicutes infection and transition and adverse pregnancy outcomes in GDM women, and to explore whether this association still exist when Mollicutes load varied. METHODS: We involved pregnant women who attended antenatal care in Chongqing, China. After inclusion and exclusion criteria, we conducted a single-center cohort study of 432 GDM women with pregnancy outcomes from January 1, 2018 to December 31, 2021. The main outcome was adverse pregnancy outcomes, including premature rupture of membrane (PROM), fetal distress, macrosomia and others. The exposure was Mollicutes infection, including Ureaplasma urealyticum (Uu) and Mycoplasma hominis (Mh) collected in both the second and the third trimesters, and testing with polymerase chain reaction method. The logistic regression models were used to estimate the relationship between Mollicutes infection and adverse pregnancy outcomes. RESULTS: Among 432 GDM women, 241 (55.79%) were infected with genital Mollicutes in either the second or third trimester of pregnancy. At the end of the pregnancy follow-up, 158 (36.57%) participants had adverse pregnancy outcomes, in which PROM, fetal distress and macrosomia were the most commonly observed adverse outcomes. Compared with the uninfected group, the Mollicutes (+/-) group showed no statistical significant increase in PROM (OR = 1.05, 95% CI:0.51 ∼ 2.08) and fetal distress (OR = 1.21, 95% CI: 0.31 ∼ 3.91). Among the 77 participants who were both Uu positive in the second and third trimesters, 38 participants presented a declined Uu load and 39 presented an increased Uu load. The Uu increased group had a 2.95 odds ratio (95% CI: 1.10~8.44) for adverse pregnancy outcomes. CONCLUSION: Mollicutes infection and transition during trimesters were not statistically associated with adverse pregnancy outcomes in GDM women. However, among those consistent infections, women with increasing Uu loads showed increased risks of adverse pregnancy outcomes. For GDM women with certain Mollicutes infection and colonization status, quantitative screening for vaginal infection at different weeks of pregnancy was recommended to provide personalized fertility treatment.

PLSDB: advancing a comprehensive database of bacterial plasmids.

Plasmids are known to contain genes encoding for virulence factors and antibiotic resistance mechanisms. Their relevance in metagenomic data processing is steadily growing. However, with the increasing popularity and scale of metagenomics experiments, the number of reported plasmids is rapidly growing as well, amassing a considerable number of false positives due to undetected misassembles. Here, our previously published database PLSDB provides a reliable resource for researchers to quickly compare their sequences against selected and annotated previous findings. Within two years, the size of this resource has more than doubled from the initial 13,789 to now 34,513 entries over the course of eight regular data updates. For this update, we aggregated community feedback for major changes to the database featuring new analysis functionality as well as performance, quality, and accessibility improvements. New filtering steps, annotations, and preprocessing of existing records improve the quality of the provided data. Additionally, new features implemented in the web-server ease user interaction and allow for a deeper understanding of custom uploaded sequences, by visualizing similarity information. Lastly, an application programming interface was implemented along with a python library, to allow remote database queries in automated workflows. The latest release of PLSDB is freely accessible under https://www.ccb.uni-saarland.de/plsdb.

CRISPR-based targeting of DNA methylation in Arabidopsis thaliana by a bacterial CG-specific DNA methyltransferase.

CRISPR-based targeted modification of epigenetic marks such as DNA cytosine methylation is an important strategy to regulate the expression of genes and their associated phenotypes. Although plants have DNA methylation in all sequence contexts (CG, CHG, CHH, where H = A, T, C), methylation in the symmetric CG context is particularly important for gene silencing and is very efficiently maintained through mitotic and meiotic cell divisions. Tools that can directly add CG methylation to specific loci are therefore highly desirable but are currently lacking in plants. Here we have developed two CRISPR-based CG-specific targeted DNA methylation systems for plants using a variant of the bacterial CG-specific DNA methyltransferase MQ1 with reduced activity but high specificity. We demonstrate that the methylation added by MQ1 is highly target specific and can be heritably maintained in the absence of the effector. These tools should be valuable both in crop engineering and in plant genetic research.

Acidaminococcus homini s sp. nov., Amedibacillus hominis sp. nov., Lientehia hominis gen. nov. sp. nov., Merdimmobilis hominis gen. nov. sp. nov., and Paraeggerthella hominis sp. nov., isolated from human faeces.

The human gastrointestinal tract is inhabited by various microorganisms, including thousands of bacterial taxa that have yet to be cultured and characterized. In this report, we describe the isolation, cultivation, genotypic and phenotypic characterization and taxonomy of five novel anaerobic bacterial strains that were recovered during the massive cultivation and isolation of gut microbes from human faecal samples. On the basis of the polyphasic taxonomic results, we propose two novel genera and five novel species. They are Acidaminococcus hominis sp. nov. (type strain NSJ-142T=CGMCC 1.17903T=KCTC 25346T), Amedibacillus hominis sp. nov. (type strain NSJ-176T=CGMCC 1.17933T=KCTC 25355T), Lientehia hominis gen. nov. sp. nov. (type strain NSJ-141T=CGMCC 1.17902T=KCTC 25345T), Merdimmobilis hominis gen. nov. sp. nov. (type strain NSJ-153T=CGMCC 1.17915T=KCTC 25350T) and Paraeggerthella hominis sp. nov. (type strain NSJ-152T=CGMCC 1.17914T=KCTC 25349T).

Prevalence of Mollicutes among men who have sex with men and transgender women aged 15 to 19 years in Salvador, North-eastern Brazil.

BACKGROUND: Some species of Mollicutes have been associated with different pathologies of the urogenital tract in humans, with a high prevalence among adult men who have sex with men (MSM) and transgender women (TGW). However, few studies have been performed to investigate its prevalence among adolescents. In this study, we estimated the initial prevalence of Mycoplasma genitalium (MG), Mycoplasma hominis (MH), Ureaplasma urealyticum (UU), and Ureaplasma parvum (UP); the rate of misdiagnosis at different anatomical sites; and the associated factors with positive tests for Mollicutes among MSM and TGW aged 15 to 19 years enrolled in the PrEP1519 study. METHODS: PrEP-1519 is the first study to investigate the effectiveness of pre-exposure prophylaxis for human immunodeficiency virus among adolescent MSM and TGW aged 15 to 19 in Latin America. Oral, anal, and urethral swabs were taken from 246 adolescents upon enrolment in the study to detect MG, MH, UU, and UP by quantitative polymerase chain reaction (qPCR). Bivariate and multivariate analyses were conducted by Poisson regression and 95% confidence intervals (95% CI) were estimated. RESULTS: The prevalence of Mollicutes was 32.1%. UU was the most prevalent species (20.7%), followed by MH (13.4%), MG (5.7%), and UP (3.2%); 67.3% of the positive samples would have been missed if only urethral samples had been taken. Receptive anal sex (prevalence ratio [PR] = 1.79; 95% CI = 1.07-3.01) and clinical suspicion of sexually transmitted infection (PR = 1.62; 95% CI = 1.01-2.61) were factors associated with the detection of Mollicutes in general. Group sex (PR = 1.98; 95% CI = 1.12-3.50) and receptive anal sex (PR = 2.36; 95% CI = 0.95-5.86) were associated with the detection of Mycoplasma spp. No sociodemographic, clinical, or behavioural variable was significantly associated with the detection of Ureaplasma spp. CONCLUSIONS: A high prevalence of Mollicutes was observed among adolescent MSM and TGW, especially at extragenital sites. Further research is required to understand the epidemiological profile of high-risk adolescents in different regions and contexts, and to investigate the pathogenesis of Mollicutes in the oral and anal mucosa before routine screening can be recommended in clinical practice.

Genome Mosaicism in Field Strains of Mycoplasma bovis as Footprints of In-Host Horizontal Chromosomal Transfer.

Horizontal gene transfer was long thought to be marginal in Mollicutes, but the capacity of some of these wall-less bacteria to exchange large chromosomal regions has been recently documented. Mycoplasma chromosomal transfer (MCT) is an unconventional mechanism that relies on the presence of a functional integrative conjugative element (ICE) in at least one partner and involves the horizontal acquisition of small and large chromosomal fragments from any part of the donor genome, which results in progenies composed of an infinite variety of mosaic genomes. The present study focuses on Mycoplasma bovis, an important pathogen of cattle responsible for major economic losses worldwide. By combining phylogenetic tree reconstructions and detailed comparative genome analyses of 36 isolates collected in Spain (2016 to 2018), we confirmed the mosaic nature of 16 field isolates and mapped chromosomal transfers exchanged between their hypothetical ancestors. This study provides evidence that MCT can take place in the field, most likely during coinfections by multiple strains. Because mobile genetic elements (MGEs) are classical contributors of genome plasticity, the presence of phages, insertion sequences (ISs), and ICEs was also investigated. Data revealed that these elements are widespread within the M. bovis species and evidenced classical horizontal transfer of phages and ICEs in addition to MCT. These events contribute to wide-genome diversity and reorganization within this species and may have a tremendous impact on diagnostic and disease control. IMPORTANCE Mycoplasma bovis is a major pathogen of cattle that has significant detrimental effects on economics and animal welfare in cattle rearing worldwide. Understanding the evolution and the adaptative potential of pathogenic mycoplasma species in the natural host is essential to combating them. In this study, we documented the occurrence of mycoplasma chromosomal transfer, an atypical mechanism of horizontal gene transfer, in field isolates of M. bovis that provide new insights into the evolution of this pathogenic species in their natural host. Although these events are expected to occur at low frequency, their impact is accountable for genome-wide variety and reorganization within M. bovis species, which may compromise both diagnostic and disease control.

Tannockella kyphosi gen. nov., sp. nov., a member of the family Erysipelotrichaceae, isolated from the hindgut of the marine herbivorous fish Kyphosus sydneyanus.

A Gram-stain-positive, non-spore-forming, rod-shaped, obligately anaerobic bacterium, designated strain BP52GT, was isolated from the hindgut of a Silver Drummer (Kyphosus sydneyanus) fish collected from the Hauraki Gulf, New Zealand. Phylogenetic analysis based on 16S rRNA gene sequencing indicated that the isolate belonged to the family Erysipelotrichaceae in the phylum Firmicutes and was most closely related to Clostridium saccharogumia with 93.3 % sequence identity. Isolate BP52GT grew on agar medium containing mannitol as the sole carbon source. White, opaque and shiny colonies of the isolate measuring approximately 1 mm diameter grew within a week at 20-28 °C (optimum, 24 °C) and pH 6.9-8.5 (optimum, pH 7.8). BP52GT tolerated the addition of up to 1 % NaCl to the medium. Formate and acetate were the major fermentation products. The major cellular fatty acids were C16 : 0, C16:1n-7t and C18:1n-7t. The genome sequence of the isolate was determined. Its G+C content was 30.7 mol%, and the 72.65 % average nucleotide identity of the BP52GT genome to its closest neighbour with a completely sequenced genome (Erysipelatoclostridium ramosum JCM 1298T) indicated low genomic relatedness. Based on the phenotypic and taxonomic characteristics observed in this study, a novel genus and species Tannockella kyphosi gen. nov., sp. nov. is proposed for isolate BP52GT (=NZRM 4757T=JCM 34692T).

Squash bees host high diversity and prevalence of parasites in the northeastern United States.

The squash bee Eucera (Peponapis) pruinosa is emerging as a model species to study how stressors impact solitary wild bees in North America. Here, we describe the prevalence of trypanosomes, microsporidians and mollicute bacteria in E. pruinosa and two other species, Bombus impatiens and Apis mellifera, that together comprise over 97% of the pollinator visitors of Cucurbita agroecosystems in Pennsylvania (United States). Our results indicate that all three parasite groups are commonly detected in these bee species, but E. pruinosa often exhibit higher prevalences. We further describe novel trypanosome parasites detected in E. pruinosa, however it is unknown how these parasites impact these bees. We suggest future work investigates parasite replication and infection outcomes.

Specific microbiota enhances intestinal IgA levels by inducing TGF-ß in T follicular helper cells of Peyer's patches in mice.

In humans and mice, mucosal immune responses are dominated by IgA antibodies and the cytokine TGF-ß, suppressing unwanted immune reactions but also targeting Ig class switching to IgA. It had been suggested that eosinophils promote the generation and maintenance of mucosal IgA-expressing plasma cells. Here, we demonstrate that not eosinophils, but specific bacteria determine mucosal IgA production. Co-housing of eosinophil-deficient mice with mice having high intestinal IgA levels, as well as the intentional microbiota transfer induces TGF-ß expression in intestinal T follicular helper cells, thereby promoting IgA class switching in Peyer's patches, enhancing IgA+ plasma cell numbers in the small intestinal lamina propria and levels of mucosal IgA. We show that bacteria highly enriched for the genus Anaeroplasma are sufficient to induce these changes and enhance IgA levels when adoptively transferred. Thus, specific members of the intestinal microbiota and not the microbiota as such regulate gut homeostasis, by promoting the expression of immune-regulatory TGF-ß and of mucosal IgA.

Dihydrouridine synthesis in tRNAs is under reductive evolution in Mollicutes.

Dihydrouridine (D) is a tRNA-modified base conserved throughout all kingdoms of life and assuming an important structural role. The conserved dihydrouridine synthases (Dus) carries out D-synthesis. DusA, DusB and DusC are bacterial members, and their substrate specificity has been determined in Escherichia coli. DusA synthesizes D20/D20a while DusB and DusC are responsible for the synthesis of D17 and D16, respectively. Here, we characterize the function of the unique dus gene encoding a DusB detected in Mollicutes, which are bacteria that evolved from a common Firmicute ancestor via massive genome reduction. Using in vitro activity tests as well as in vivo E. coli complementation assays with the enzyme from Mycoplasma capricolum (DusBMCap), a model organism for the study of these parasitic bacteria, we show that, as expected for a DusB homolog, DusBMCap modifies U17 to D17 but also synthetizes D20/D20a combining therefore both E. coli DusA and DusB activities. Hence, this is the first case of a Dus enzyme able to modify up to three different sites as well as the first example of a tRNA-modifying enzyme that can modify bases present on the two opposite sides of an RNA-loop structure. Comparative analysis of the distribution of DusB homologs in Firmicutes revealed the existence of three DusB subgroups namely DusB1, DusB2 and DusB3. The first two subgroups were likely present in the Firmicute ancestor, and Mollicutes have retained DusB1 and lost DusB2. Altogether, our results suggest that the multisite specificity of the M. capricolum DusB enzyme could be an ancestral property.

Taxonomy, not locality, influences the cloacal microbiota of two nearctic colubrids: a preliminary analysis.

BACKGROUND: The gut microbiota is an emerging frontier in wildlife research and its importance to vertebrate health and physiology is becoming ever more apparent. Reptiles, in particular snakes, have not received the same attention given to other vertebrates and the composition of their wild gut microbiome remains understudied. The primary goal of this work was to describe the cloacal microbiota of two Colubrids, the Eastern Gartersnake (Thamnophis sirtalis sirtalis) and the Northern Watersnake (Nerodia sipedon sipedon), and if their cloacal microbiota differed as well as if it did between a wetland and upland population of the former species. METHODS AND RESULTS: We utilized next-generation sequencing of cloacal swabs-a non-destructive proxy for the gut microbiota. The cloacal microbiome of Eastern Gartersnakes (N = 9) was like those of other snakes being comprised of Proteobacteria, Bacteroidetes, and Firmicutes, while that of Northern Watersnakes (N = 6) was dominated by Tenericutes. Seven microbial operational taxonomic units (OTUs), all members of Proteobacteria, were shared among all individuals and were indicative of a core microbiome in Eastern Gartersnakes, but these OTUs were not particularly relevant to Northern Watersnakes. The latter had greater OTU richness than did Eastern Gartersnakes, and habitat did not have any apparent effect on the microbial community composition in Eastern Gartersnakes. CONCLUSIONS: Our findings suggest host taxonomy to be a determining factor in the cloacal microbiota of snakes and that Tenericutes are associated with aquatic habitats. This is the first report to examine the cloacal microbiome of these species and provides a useful foundation for future work to build upon.

Identification of Mycoplasma species and related organisms from ruminants in England and Wales during 2005-2019.

BACKGROUND: Mycoplasma species have been associated with economically important diseases affecting ruminants worldwide and include contagious bovine pleuropneumonia (CBPP), contagious caprine pleuropneumonia (CCPP) and contagious agalactia, listed by the World Organisation for Animal Health (OIE). The Mycoplasma Team at the Animal and Plant Health Agency provides an identification service for Mycoplasma and Ureaplasma species of veterinary importance to the United Kingdom (UK), supporting the detection of new and emerging pathogens, as well as contributing to the surveillance of endemic, and the OIE listed diseases exotic to the UK. Mycoplasma and other Mollicutes species were identified from diagnostic samples from farmed ruminants in England and Wales using a combination of culture and 16S rRNA gene-based PCR-denaturing gradient gel electrophoresis, submitted between 2005 and 2019. RESULTS: A total of 5578 mollicutes identifications, which include mycoplasmas and the related acholeoplasmas and ureaplasmas, were made from farmed ruminant animals during the study period. Throughout the study period, the pathogen Mycoplasma bovis was consistently the most frequently identified species, accounting for 1411 (32%) of 4447 molecular identifications in cattle, primarily detected in the lungs of pneumonic calves, followed by joints and milk of cattle showing signs of arthritis and mastitis, respectively. M. bovirhinis, M. alkalescens, M. dispar, M. arginini and Ureaplasma diversum, were also common. Mixed species, principally M. bovis with M. alkalescens, M. arginini or M. bovirhinis were also prevalent, particularly from respiratory samples. The non-cultivable blood-borne haemoplasmas Candidatus 'Mycoplasma haemobos' and Mycoplasma wenyonii were identified from cattle, with the latter species most often associated with milk-drop. M. ovipneumoniae was the predominant species identified from sheep and goats experiencing respiratory disease, while M. conjunctivae preponderated in ocular samples. The UK remains free of the ruminant mycoplasmas listed by OIE. CONCLUSIONS: The continued high prevalence of M. bovis identifications confirms its ongoing dominance and importance as a significant pathogen of cattle in England and Wales, particularly in association with respiratory disease. M. ovipneumoniae has seen a general increase in prevalence in recent years, notably in coughing lambs and should therefore be considered as a primary differential diagnosis of respiratory disease in small ruminants.

Identification of contaminating mollicutes in mammalian cell culture as spiroplasma species.

Cell cultures have provided an ideal habitat for a wide variety of Mycoplasma and Acholeplasma species since the earliest days of in-vitro culture. The possibility of contamination with Spiroplasma species was addressed by Regulatory Authorities due to the increased commercial use of insect cells, recognising that Spiroplasmas have been isolated from many types of arthropod and also that insect cell cultures support Spiroplasma growth as they have been used for cultivation of fastidious species. In this study we re-examined two cell culture samples previously confirmed as contaminated with mollicutes by cultural methods. One isolate had undergone sequencing which had placed it in the S. citri phylogenetic group, whilst the other had not been identified. Using modern sequencing methods we were able to further identify both isolates to species level.

Flow-Cytometric Method for Viability Analysis of Mycoplasma gallisepticum and Other Cell-Culture-Contaminant Mollicutes.

Mycoplasma is the smallest self-replicating bacteria, figuring as common contaminant of eukaryotic cell cultures. Production inputs and operator's manipulation seem to be the main sources of such contamination. Many analytical approaches have been applied for mycoplasma detection in cell cultures and also in biological products. However, unless they were validated, only indicator cell culture and bacteriological culture are considered as compendial methods for quality control of biological products. Nano-flow cytometry has been pointed out as an alternative technique for addressing prokaryotic and eukaryotic cell viability being a substantial tool for reference material production. In this study, a viability-flow-cytometry assay was standardized for M. gallisepticum and then applied to other cell-culture-contaminant mycoplasmas. For this, M. galliseticum's growth rate was observed and different treatments were evaluated to establish low viability cultures (cell death-induced control). Distinct viability markers and their ideal concentrations (titration) were appraised. Ethanol treatment showed to be the best death-inducing control. CFDA and TOPRO markers revealed to be the best choice for detecting live and dead mycoplasma frequencies, respectively. The standardized methodology was applied to Mycoplasma arginini, M. hyorhinis, M. orale, Spiroplasma citri and Acholeplasma laidlawii. Significant statistical difference was observed in the percentage of viable cells in comparison to ethanol treatment for A. laidlawii in CFDA and in both markers for M. gallisepticum, M. hyorhinis and S. citri. In summary, we standardized a flow cytometry assay for assessing M. gallisepticum - and potentially other species - viability and ultimately applied for reference material production improving the quality control of biological products.

Phylogenomics of expanding uncultured environmental Tenericutes provides insights into their pathogenicity and evolutionary relationship with Bacilli.

BACKGROUND: The metabolic capacity, stress response and evolution of uncultured environmental Tenericutes have remained elusive, since previous studies have been largely focused on pathogenic species. In this study, we expanded analyses on Tenericutes lineages that inhabit various environments using a collection of 840 genomes. RESULTS: Several environmental lineages were discovered inhabiting the human gut, ground water, bioreactors and hypersaline lake and spanning the Haloplasmatales and Mycoplasmatales orders. A phylogenomics analysis of Bacilli and Tenericutes genomes revealed that some uncultured Tenericutes are affiliated with novel clades in Bacilli, such as RF39, RFN20 and ML615. Erysipelotrichales and two major gut lineages, RF39 and RFN20, were found to be neighboring clades of Mycoplasmatales. We detected habitat-specific functional patterns between the pathogenic, gut and the environmental Tenericutes, where genes involved in carbohydrate storage, carbon fixation, mutation repair, environmental response and amino acid cleavage are overrepresented in the genomes of environmental lineages, perhaps as a result of environmental adaptation. We hypothesize that the two major gut lineages, namely RF39 and RFN20, are probably acetate and hydrogen producers. Furthermore, deteriorating capacity of bactoprenol synthesis for cell wall peptidoglycan precursors secretion is a potential adaptive strategy employed by these lineages in response to the gut environment. CONCLUSIONS: This study uncovers the characteristic functions of environmental Tenericutes and their relationships with Bacilli, which sheds new light onto the pathogenicity and evolutionary processes of Mycoplasmatales.

A timetree for phytoplasmas (Mollicutes) with new insights on patterns of evolution and diversification.

The first comprehensive timetree is presented for phytoplasmas, a diverse group of obligate intracellular bacteria restricted to phloem sieve elements of vascular plants and tissues of their hemipteran insect vectors. Maximum likelihood-based phylogenetic analysis of DNA sequence data from the 16S rRNA and methionine aminopeptidase (map) genes yielded well resolved estimates of phylogenetic relationships among major phytoplasma lineages, 16Sr groups and known strains of phytoplasmas. Age estimates for divergences among two major lineages of Mollicutes based on a previous comprehensive bacterial timetree were used to calibrate an initial 16S timetree. A separate timetree was estimated based on the more rapidly-evolving map gene, with an internal calibration based on a recent divergence within two related 16Sr phytoplasma subgroups in group 16SrV thought to have been driven by the introduction of the North American leafhopper vector Scaphoideus titanus Ball into Europe during the early part of the 20th century. Combining the resulting divergence time estimates into a final 16S timetree suggests that evolutionary rates have remained relatively constant overall through the evolution of phytoplasmas and that the origin of this lineage, at ~641 million years ago (Ma), preceded the origin of land plants and hemipteran insects. Nevertheless, the crown group of phytoplasmas is estimated to have begun diversifying ~316 Ma, roughly coinciding with the origin of seed plants and Hemiptera. Some phytoplasma groups apparently associated with particular plant families or insect vector lineages generally arose more recently than their respective hosts and vectors, suggesting that vector-mediated host shifts have been an important mechanism in the evolutionary diversification of phytoplasmas. Further progress in understanding macroevolutionary patterns in phytoplasmas is hindered by large gaps in knowledge of the identity of competent vectors and lack of data on phytoplasma associations with non-economically important plants.

Metagenomic profiling of bacterial diversity and community structure in termite mounds and surrounding soils.

The study focuses on analysis of the compositional and diversity of bacteria in termite mound soils in comparison with the surrounding soils to verify the assertion that the high nutrient concentrations in termite mound soils influence a complex diversity of microorganisms. Here, whole DNA was extracted from soil samples collected from termite mounds and their surrounding soils which were 10 m apart and subsequently, sequenced using shotgun metagenomic approach. Our findings showed that both environments have several soil bacterial phyla in common. However, Proteobacteria and Actinobacteria significantly dominated the termite mound soils and the surrounding soils, respectively, with Tenericutes peculiar to only the termite mound soils. Furthermore, Bergeyella, Gloeothece, Thalassospira, and Glaciecola genera were exclusively identified in the termite mound soil samples. Diversity analysis showed that bacterial composition was different among the four sites (phyla level). This study also revealed a lot of unclassified groups of bacteria and this could point to the presence of potentially novel species. The differences observed in the bacterial structure and diversity from this study may be ascribed to variances in the physicochemical nature existing between the two environments. Mapping out schemes to culture these unclassified groups of bacteria discovered from this study would possibly set the platform for the discovery of novel bacteria for biotechnological applications.

Necessity and rationale for the proposed name changes in the classification of Mollicutes species. Reply to: 'Recommended rejection of the names Malacoplasma gen. nov., Mesomycoplasma gen. nov., Metamycoplasma gen. nov., Metamycoplasmataceae fam. nov., Mycoplasmoidaceae fam. nov., Mycoplasmoidales ord. nov., Mycoplasmoides gen. nov., Mycoplasmopsis gen. nov. [Gupta, Sawnani, Adeolu, Alnajar and Oren 2018] and all proposed species comb. nov. placed therein', by M. Balish et al. (Int J Syst Evol Microbiol, 2019;69:3650-3653).

This response summarizes the highly disordered state of the Mollicutes taxonomy that existed until recently, where most Mollicutes taxa lacked proper circumscriptions and their names were not in accordance with the International Code of Nomenclature of Prokaryotes and illegitimate. We also summarize the comprehensive phylogenomic and comparative genomic studies forming the basis for the proposed changes in the classification of Mollicultes species. Our responses to the concerns raised by Balish et al., show that the proposed taxonomic changes do not violate any essential point of the Code. Instead the proposed name changes rectify numerous taxonomic anomalies that have long plagued the classification of Mollicutes species, leading to a better understanding of their evolutionary relationships and bringing their nomenclature in conformity with the Code.

Prevalence and antibiotic resistance of rectal Mollicutes in HIV-infected men who have sex with men at the University Hospital of Dresden, Germany.

BACKGROUND: Rectal sexually transmitted infections (STI) are common in men having sex with men (MSM). Mycoplasma genitalium is increasingly being reported in this localization, but due to frequent lack of symptoms at this site, clinical significance is still unclear. Rectal prevalence of Mycoplasma hominis and Ureaplasma species is not well studied so far. We aimed to investigate the prevalence and antibiotic sensitivity of rectal Mollicutes in our HIV-cohort. METHODS: In 227 MSM presenting for annual STI-screening, 317 anorectal swabs were collected from January 2017 to December 2018. PCR was performed for detection of Chlamydia trachomatis, Neisseria gonorrhoeae, M. genitalium and also culture for M. hominis and Ureaplasma spec. RESULTS: Prevalence for M. genitalium, M. hominis, Ureaplasma spec., C. trachomatis and N. gonorrhoeae was 8.2%, 7.3%, 12.0%, 5.1% and 1.9%, respectively. Patients were asymptomatic with few exceptions. Seroprevalence of syphilis in 227 MSM was 41.9%. In 20 strains of M. genitalium, resistance-associated mutations to macrolides and quinolones were found in 60% and 30%, respectively; in five strains (25%) to both. M. hominis and Ureaplasma spec. frequently occurred combined, mostly in significant quantity consistent with infection. M. hominis and Ureaplasma spec. regularly showed sensitivity to tetracycline. CONCLUSION: At screening, rectal colonization with Mollicutes was common in our patients, but rarely caused symptoms. Due to rising antibiotic resistance of M. genitalium against quinolones, therapeutic options are increasingly limited. Treatment should be guided by antibiotic resistance testing including quinolones. In persisting anorectal symptoms, M. hominis and Ureaplasma spec. should also be taken into account.

Mycoplasma bovis and other Mollicutes in replacement dairy heifers from Mycoplasma bovis-infected and uninfected herds: A 2-year longitudinal study.

Replacement dairy heifers exposed to Mycoplasma bovis as calves may be at risk of future clinical disease and pathogen transmission, both within and between herds; however, little information is available about these risks. We conducted a 2-yr longitudinal (panel) study starting with 450 heifer calves reared to weaning in 8 herds (7 M. bovis infected with clinical disease, 1 uninfected) under the same ownership. After weaning, heifers were commingled and managed with non-study heifers at a single heifer rearing facility. Nose, conjunctival, and vaginal swabs were collected along with a blood sample at weaning, prebreeding, precalving, and approximately 1 mo postcalving. Additionally, a colostrum sample was collected upon calving and a composite milk sample was collected 1 mo postcalving. The swabs, colostrum, and milk samples were cultured for Mycoplasma spp., and serum from the blood was evaluated for serological evidence of exposure to M. bovis using an ELISA. Despite a high M. bovis ELISA seroprevalence at weaning in the heifers from the 7 M. bovis-infected herds with clinical disease [72% (289/400); range by herd: 28-98%], M. bovis was isolated from only 4% (16/400) of the same heifers at the same time. In heifers from the uninfected herd at weaning, M. bovis seroprevalence was 2% (1/50) and M. bovis was not detected by culture. Mycoplasma bovis was isolated from 0.5% (2/414) of heifers at prebreeding, 0% (0/374) of heifers at precalving, and 0.3% (1/356) of heifers 1 mo postcalving. The nose was the predominant anatomical site of M. bovis colonization (74%; 14/19 culture positives). A single heifer (from an M. bovis-infected herd with clinical disease) was repeatedly detected with M. bovis in its nose at weaning, prebreeding, and postcalving samplings. This demonstrates the possibility, albeit rare, of a long-term M. bovis carrier state in replacement heifers exposed to M. bovis as calves, up to at least 1 mo after entry into the milking herd. No M. bovis clinical disease was detected in any heifer from weaning through to the end of the study (approximately 1 mo after calving). Acholeplasma spp. were commonly isolated throughout the study. Mycoplasma bovigenitalium, Mycoplasma bovoculi, and Mycoplasma bovirhinis were isolated infrequently. Mycoplasma bovis seroprevalences at prebreeding, precalving, and postcalving samplings were 27% (112/414), 12% (46/374), and 18% (65/356), respectively. Overall, the results show that replacement heifers from groups exposed to M. bovis preweaning can become colonized with M. bovis and that colonization can, uncommonly, be present after their first calving. For groups of 50 or more heifers exposed to M. bovis preweaning, there is at least a nontrivial probability that the group will contain at least 1 shedding heifer postcalving.