Evaluation of Metronidazole Resistance of Vaginal Swab Isolates from South African Women Treated for Bacterial Vaginosis.

: The high recurrence rate of bacterial vaginosis (BV) after antibiotic treatment is at least partially attributed to resistant bacteria. The CAPRISA 083 (CAP083) study investigated the influence of metronidazole (MTZ) treatment on the vaginal microbiome in 56 South African women diagnosed with BV. To explore the etiology of recurrent BV in this cohort, we retrospectively analyzed vaginal swabs collected in CAP083 before and after MTZ treatment.

SepT, a novel protein specific to multicellular cyanobacteria, influences peptidoglycan growth and septal nanopore formation in sp. PCC 7120.

Multicellular organization is a requirement for the development of complex organisms, and filamentous cyanobacteria such as represent a paradigmatic case of bacterial multicellularity. The filament can include hundreds of communicated cells that exchange nutrients and regulators and, depending on environmental conditions, can include different cell types specialized in distinct biological functions. Hence, the specific features of the filament and how they are propagated during cell division represent outstanding biological issues.

SepN is a septal junction component required for gated cell-cell communication in the filamentous cyanobacterium Nostoc.

Multicellular organisms require controlled intercellular communication for their survival. Strains of the filamentous cyanobacterium Nostoc regulate cell-cell communication between sister cells via a conformational change in septal junctions. These multi-protein cell junctions consist of a septum spanning tube with a membrane-embedded plug at both ends, and a cap covering the plug on the cytoplasmic side.

Structure of a thylakoid-anchored contractile injection system in multicellular cyanobacteria.

Contractile injection systems (CISs) mediate cell-cell interactions by phage tail-like structures, using two distinct modes of action: extracellular CISs are released into the medium, while type 6 secretion systems (T6SSs) are attached to the cytoplasmic membrane and function upon cell-cell contact. Here, we characterized a CIS in the multicellular cyanobacterium Anabaena, with features distinct from extracellular CISs and T6SSs. Cryo-electron tomography of focused ion beam-milled cells revealed that CISs were anchored in thylakoid membrane stacks, facing the cell periphery.

Plasmid-Chromosome Crosstalk in : A Horizontally Acquired Transcription Regulator Controls Polysaccharide Intercellular Adhesin-Mediated Biofilm Formation.

Livestock-associated methicillin-resistant (LA-MRSA) of clonal complex CC398 typically carry various antimicrobial resistance genes, many of them located on plasmids. In the bovine LA-MRSA isolate Rd11, we previously identified plasmid pAFS11 in which resistance genes are co-localized with a novel -like gene cluster, harboring genes required for polysaccharide intercellular adhesin (PIA)-mediated biofilm formation. The genes on pAFS11 were acquired in addition to a pre-existing locus on the  Rd11 chromosomal DNA.

Cell-cell communication through septal junctions in filamentous cyanobacteria.

Septal junctions are cell-cell connections that mediate intercellular communication in filamentous cyanobacteria. The septal peptidoglycan is perforated by dozens of 20 nm-wide nanopores, through which these proteinaceous structures traverse, physically connecting adjacent cells. On each cytoplasmic side, every septal junction contains a flexible cap structure that closes the connection in a reversible manner upon stress.

A nanopore array in the septal peptidoglycan hosts gated septal junctions for cell-cell communication in multicellular cyanobacteria.

Some filamentous cyanobacteria are phototrophic bacteria with a true multicellular life style. They show patterned cell differentiation with the distribution of metabolic tasks between different cell types. This life style requires a system of cell-cell communication and metabolite exchange along the filament.

Structure and Function of a Bacterial Gap Junction Analog.

Multicellular lifestyle requires cell-cell connections. In multicellular cyanobacteria, septal junctions enable molecular exchange between sister cells and are required for cellular differentiation. The structure of septal junctions is poorly understood, and it is unknown whether they are capable of controlling intercellular communication.

Direct activation of a phospholipase by cyclic GMP-AMP in El Tor .

Sensing and responding to environmental changes is essential for bacteria to adapt and thrive, and nucleotide-derived second messengers are central signaling systems in this process. The most recently identified bacterial cyclic dinucleotide second messenger, 3', 3'-cyclic GMP-AMP (cGAMP), was first discovered in the El Tor biotype of The cGAMP synthase, DncV, is encoded on the VSP-1 pathogenicity island, which is found in all El Tor isolates that are responsible for the current seventh pandemic of cholera but not in the classical biotype. We determined that unregulated production of DncV inhibits growth in El Tor but has no effect on the classical biotype.