Capsular Polysaccharide Production in Bacteria of the Mycoplasma Genus: A Huge Diversity of Pathways and Synthases for So-Called Minimal Bacteria.

Mycoplasmas are wall-less bacteria with many species spread across various animal hosts in which they can be pathogenic. Despite their reduced anabolic capacity, some mycoplasmas are known to secrete hetero- and homopolysaccharides, which play a role in host colonization through biofilm formation or immune evasion, for instance. This study explores how widespread the phenomenon of capsular homopolysaccharide secretion is within mycoplasmas, and investigates the diversity of both the molecules produced and the synthase-type glycosyltransferases responsible for their production.

Unravelling the main genomic features of Mycoplasma equirhinis.

Background: Mycoplasma spp. are wall-less bacteria with small genomes (usually 0.5-1.

Epidemiology and pathogenicity of M. equirhinis in equine respiratory disorders.

Mycoplasmas are pathogens involved in respiratory disorders of various animal hosts. In horses, Mycoplasma (M.) equirhinis is the species most frequently detected in clinical respiratory specimens, with a prevalence of 12-16%, but its clinical implication in equine respiratory disorders remains unclear.

Comparative genomics of , a fast-growing pathogen of wild .

is a fast-growing species isolated from wild and first described in 2013. isolates have been associated with arthritis, kerato conjunctivitis, pneumonia and septicemia, but were also recovered from apparently healthy animals. To better understand what defines this species, we performed a genomic survey on 14 strains collected from free-ranging or zoo-housed animals between 1987 and 2017, mostly in Europe.

Genome-wide phylodynamic approach reveals the epidemic dynamics of the main subtype circulating in France.

is a major aetiological agent of bovine respiratory disease worldwide. Genome-based analyses are increasingly being used to monitor the genetic diversity and global distribution of , complementing existing subtyping schemes based on locus sequencing. However, these analyses have so far provided limited information on the spatiotemporal and population dynamics of circulating subtypes.

Detection of Mycoplasma spp. in horses with respiratory disorders.

Background: Bacteria belonging to the genus Mycoplasma are small-sized, have no cell walls and small genomes. They commonly cause respiratory disorders in their animal hosts. Three species have been found in the respiratory tract of horses worldwide, that is.

Genomic features of Mycoplasma bovis subtypes currently circulating in France.

Background: Mycoplasma (M.) bovis is a major etiological agent of bovine respiratory disease, which is the most economically costly disease of cattle worldwide. Cattle disease surveillance on M.

Prevalence of in Algeria and Characterisation of the Isolated Clones.

Bovine respiratory disease (BRD) is common in calves in Algeria, but to date, has never been monitored as a potential etiological agent. Here, to assess the presence (direct detection) and circulation (indirect detection) of , broncho-alveolar lavage fluids (BALF) and serum samples were collected from 60 veal calf farms in Algeria. A commercial ELISA kit (ID Screen ELISA) was used to screen for the presence of specific antibodies against .

The spp. 'Releasome': A New Concept for a Long-Known Phenomenon.

The bacterial secretome comprises polypeptides expressed at the cell surface or released into the extracellular environment as well as the corresponding secretion machineries. Despite their reduced coding capacities, spp. are able to produce and release several components into their environment, including polypeptides, exopolysaccharides and extracellular vesicles.

Integrating the Human and Animal Sides of Mycoplasmas Resistance to Antimicrobials.

Mycoplasma infections are frequent in humans, as well as in a broad range of animals. However, antimicrobial treatment options are limited, partly due to the lack of a cell wall in these peculiar bacteria. Both veterinary and human medicines are facing increasing resistance prevalence for the most commonly used drugs, despite different usage practices.

Efflux Might Participate in Decreased Susceptibility to Oxytetracycline in Contagious Agalactia-Causative spp.

Contagious agalactia is associated with mastitis, keratoconjunctivitis, arthritis, pneumonia, and septicemia in small ruminants in countries with large dairy industries worldwide. The causative agents belong to four (sub)species of the genus that have remained essentially susceptible to antimicrobials, including to the widely-used tetracycline family. However, some clinical isolates have been detected that show increased minimum inhibitory concentrations of tetracyclines, although they do not harbor the mutation in the 16SrRNA gene usually associated with resistance.

Addressing the Antimicrobial Resistance of Ruminant Mycoplasmas Using a Clinical Surveillance Network.

Antimicrobial resistance (AMR) surveillance of mycoplasmas of veterinary importance has been held back for years due to lack of harmonized methods for antimicrobial susceptibility testing (AST) and interpretative criteria, resulting in a crucial shortage of data. To address AMR in ruminant mycoplasmas, we mobilized a long-established clinical surveillance network called "Vigimyc." Here we describe our surveillance strategy and detail the results obtained during a 2-year monitoring period.

in Nordic European Countries: Emergence and Dominance of a New Clone.

(.) is an important pathogen of cattle implicated in a broad range of clinical manifestations that adversely impacts livestock production worldwide. In the absence of a safe, effective commercial vaccine in Europe, the reported reduced susceptibility to antimicrobials for this organism has contributed to difficulties in controlling infection.

Population structure and antimicrobial susceptibility of Mycoplasma ovipneumoniae isolates in France.

Chronic non-progressive pneumonia in small ruminants caused by Mycoplasma (M.) ovipneumoniae is mainly controlled by chemotherapy. In France, during the last decade, a rise in M.

Mycoplasma hyopneumoniae J elicits an antioxidant response and decreases the expression of ciliary genes in infected swine epithelial cells.

Mycoplasma hyopneumoniae is the most costly pathogen for swine production. Although several studies have focused on the host-bacterium association, little is known about the changes in gene expression of swine cells upon infection. To improve our understanding of this interaction, we infected swine epithelial NPTr cells with M.

Monitoring Diversity and Antimicrobial Susceptibility in Calf Feedlots Undergoing a Respiratory Disease Outbreak.

Bovine respiratory diseases (BRD) are widespread in veal calf feedlots. Several pathogens are implicated, both viruses and bacteria, one of which, , is under-researched. This worldwide-distributed bacterium has been shown to be highly resistant in vitro to the main antimicrobials used to treat BRD.

A dataset on above- and below-ground traits of 21 species found in banana cropping systems, cultivated individually.

The data presented in this article describe 21 species that can be found in banana cropping systems: 17 cover crops species, 2 spontaneous species and 2 cultivars of banana. The cover crop species belongs mainly to Fabaceae family, but also to Poaceae, Euphorbiacea and Asteraceae. Four repetition of each species were cultivated individually, in the field, under non-limiting conditions.

High-Throughput Sequencing (HTS) of newly synthetized RNAs enables one shot detection and identification of live mycoplasmas and differentiation from inert nucleic acids.

Mycoplasma contamination threatens both the safety of biologics produced in cell substrates as well as the quality of scientific results based on cell-culture observations. Methods currently used to detect contamination of cells include culture, enzymatic activity, immunofluorescence and PCR but suffer from some limitations. High throughput sequencing (HTS) can be used to identify microbes like mycoplasmas in biologics since it enables an unbiased approach to detection without the need to design specific primers to pre-amplify target sequences but it does not enable the confirmation of microbial infection since this could reflect carryover of inert sequences.

Contagious Agalactia In Sheep And Goats: Current Perspectives.

Contagious agalactia (CA) is a disease caused equally by four species, in single or mixed infections. Clinical signs are multiple, including mastitis, arthritis, keratoconjunctivitis, pneumonia, and septicemia, non-specific, and expressed differently depending whether sheep or goats are affected, on causative mycoplasmas as well as type of husbandry. CA has been reported worldwide and its geographic distribution maps to that of small ruminant breeding areas.

Mycoplasma Chromosomal Transfer: A Distributive, Conjugative Process Creating an Infinite Variety of Mosaic Genomes.

The capacity of Mycoplasmas to engage in horizontal gene transfers has recently been highlighted. Despite their small genome, some of these wall-less bacteria are able to exchange multiple, large portions of their chromosome via a conjugative mechanism that does not conform to canonical Hfr/ models. To understand the exact features underlying mycoplasma chromosomal transfer (MCT), extensive genomic analyses were performed at the nucleotide level, using individual mating progenies derived from our model organism, .

A European inter-laboratory trial to evaluate the performance of three serological methods for diagnosis of Mycoplasma bovis infection in cattle using latent class analysis.

Background: Mycoplasma bovis (M. bovis) is an emerging bovine pathogen, leading to significant economic losses in the livestock industry worldwide. Infection can result in a variety of clinical signs, such as arthritis, pneumonia, mastitis and keratoconjunctivitis, none of which are M.

Proteases as Secreted Exoproteins in Mycoplasmas from Ruminant Lungs and Their Impact on Surface-Exposed Proteins.

Many mycoplasma species are isolated from the ruminant lungs as either saprophytes or true pathogens. These wall-less bacteria possess a minimal genome and reduced metabolic capabilities. Accordingly, they rely heavily on their hosts for the supply of essential metabolites and, notably, peptides.

A European interlaboratory trial to evaluate the performance of different PCR methods for Mycoplasma bovis diagnosis.

Background: Several species-specific PCR assays, based on a variety of target genes are currently used in the diagnosis of Mycoplasma bovis infections in cattle herds with respiratory diseases and/or mastitis. With this diversity of methods, and the development of new methods and formats, regular performance comparisons are required to ascertain diagnostic quality. The present study compares PCR methods that are currently used in six national veterinary institutes across Europe.

Mycoplasmas under experimental antimicrobial selection: The unpredicted contribution of horizontal chromosomal transfer.

Horizontal Gene Transfer was long thought to be marginal in Mycoplasma a large group of wall-less bacteria often portrayed as minimal cells because of their reduced genomes (ca. 0.5 to 2.

Mycoplasmas are no exception to extracellular vesicles release: Revisiting old concepts.

Release of extracellular vesicles (EV) by Gram-negative and positive bacteria is being frequently reported. EV are nano-sized, membrane-derived, non-self-replicating, spherical structures shed into the extracellular environment that could play a role in bacteria-host interactions. Evidence of EV production in bacteria belonging to the class Mollicutes, which are wall-less, is mainly restricted to the genus Acholeplasma and is scanty for the Mycoplasma genus that comprises major human and animal pathogens.