A Marine Group A isolate relies on other growing bacteria for cell wall formation.

Most of Earth's prokaryotes live under energy limitation, yet the full breadth of strategies that enable survival under such conditions remain poorly understood. Here we report the isolation of a bacterial strain, IA91, belonging to the candidate phylum Marine Group A (SAR406 or 'Candidatus Marinimicrobia') that is unable to synthesize the central cell wall compound peptidoglycan itself. Using cultivation experiments and microscopy, we show that IA91 growth and cell shape depend on other bacteria, deriving peptidoglycan, energy and carbon from exogenous muropeptide cell wall fragments released from growing bacteria.

Atrimonas thermophila gen. nov., sp. nov., a novel anaerobic thermophilic bacterium of the phylum Atribacterota isolated from deep subsurface gas field and proposal of Atrimonadaceae fam. nov. within the class Atribacteria in the phylum Atribacterota.

A novel anaerobic, thermophilic bacterium of the class Atribacteria, strain M15, was isolated from a high-temperature gas reservoir, Japan. Cells of strain M15 were gram-negative, short oval-shaped, and lacked flagella. Growth occurred at 45-75 °C (optimum 70-75 °C) and pH 6.

Identification and cultivation of anaerobic bacterial scavengers of dead cells.

The cycle of life and death and Earth's carbon cycle(s) are intimately linked, yet how bacterial cells, one of the largest pools of biomass on Earth, are recycled back into the carbon cycle remains enigmatic. In particular, no bacteria capable of scavenging dead cells in oxygen-depleted environments have been reported thus far. In this study, we discover the first anaerobes that scavenge dead cells and the two isolated strains use distinct strategies.

Complete Genome Sequence of sp. Strain GSA-30, a Predominant Endophytic Bacterium of Plants.

We report a complete genome sequence of sp. strain GSA-30, a predominant endophytic bacterium of plants. The genome consists of a circular 5,501,810-bp chromosome with a G+C content of 61.

Complete Genome Sequence of sp. Strain GSB-24, Isolated from inside Roots.

Here, we report a complete genome sequence of sp. strain GSB-24, an endophytic bacterium of plants. The genome consists of a circular 5,286,830-bp chromosome with a G+C content of 33.

gen. nov., sp. nov., and gen. nov., sp. nov., novel lactate-producing bacteria isolated from mouse intestines, and an emended description of the family .

Two strictly anaerobic, Gram-stain-positive, non-motile bacteria (strains OPF53 and TOC12) were isolated from mouse intestines. Strains OPF53 and TOC12 grew at pH 5.5-9.

Bile Salt Hydrolases with Extended Substrate Specificity Confer a High Level of Resistance to Bile Toxicity on Atopobiaceae Bacteria.

The bile resistance of intestinal bacteria is among the key factors responsible for their successful colonization of and survival in the mammalian gastrointestinal tract. In this study, we demonstrated that lactate-producing Atopobiaceae bacteria ( TOC12 and OPF53) isolated from mouse intestine showed high resistance to mammalian bile extracts, due to significant bile salt hydrolase (BSH) activity. We further succeeded in isolating BSH proteins (designated LcBSH and GfBSH) from TOC12 and OPF53, respectively, and characterized their enzymatic features.

Phage Genes Induce Quorum Sensing Signal Release through Membrane Vesicle Formation.

Membrane vesicles (MVs) released from the bacterium Paracoccus denitrificans Pd1222 are enriched with the quorum sensing (QS) signaling molecule N-hexadecanoyl-l-homoserine lactone (C16-HSL). However, the biogenesis of MVs in Pd1222 remains unclear. Investigations on MV formation are crucial for obtaining a more detailed understanding of the dynamics of MV-assisted signaling.

Complete Genome Sequence of Lactobacillus helveticus JCM 1004, an Aminopeptidase-Producing Lactic Acid Bacterium.

We report the complete genome sequence of Lactobacillus helveticus JCM 1004, an aminopeptidase-producing lactic acid bacterium. The genome consists of a circular chromosome which comprises 2,261,280 bp, with a G+C content of 37.56%.

Complete Genome Sequence of Bacterium Strain P1, Isolated from Mouse Feces.

bacterium strain P1 (, ) was isolated from mouse feces. Here, we report the complete genome sequence of this strain, which has a total size of 2,028,478 bp and a G+C content of 58.6%.

Identification of Bile Salt Hydrolase and Bile Salt Resistance in a Probiotic Bacterium JCM1131.

is one of the most likely probiotic candidates among many species. Although bile salt resistance has been defined as an important criterion for selection of probiotic candidates since it allows probiotic bacteria to survive in the gut, both its capability and its related enzyme, bile salt hydrolase (BSH), in is still largely unknown. Here, we report that the well-known probiotic bacterium JCM1131 possesses BSH activity and bile salt resistance capability.

Complete Genome Sequence of Anaerostipes caccae Strain L1-92, a Butyrate-Producing Bacterium Isolated from Human Feces.

strain L1-92 is a well-known butyrate-producing bacterium that has been isolated from human feces. In this announcement, we present the complete genome sequence of strain L1-92, which comprises 3,590,719 bp with a G+C content of 44.30%.

Involvement of membrane vesicles in long-chain-AHL delivery in Paracoccus species.

Bacteria are known to communicate with each other through signalling molecules that regulate gene expression within the population. However, the way in which hydrophobic signals are released and transmitted among bacterial population is not well understood. Recent studies show that membrane vesicles (MVs) are involved in delivering hydrophobic signals, such as in N-hexadecanoyl-l-homoserine lactone (C16-HSL) signalling in Paracoccus denitrificans Pd1222.

Peculiarities of biofilm formation by Paracoccus denitrificans.

Most bacteria form biofilms, which are thick multicellular communities covered in extracellular matrix. Biofilms can become thick enough to be even observed by the naked eye, and biofilm formation is a tightly regulated process. Paracoccus denitrificans is a non-motile, Gram-negative bacterium that forms a very thin, unique biofilm.

Polyfunctional Nanofibril Appendages Mediate Attachment, Filamentation, and Filament Adaptability in .

is a species of Fe/Mn-oxidizing bacteria known to form long filaments composed of chains of cells that eventually produce a rigid tube surrounding the filament. Prior to the formation of this brittle microtube, cells secrete hair-like structures from the cell surface, called nanofibrils, which develop into a soft sheath that surrounds the filament. To clarify the role of nanofibrils in filament formation in SP-6, we analyze the behavior of individual cells and multicellular filaments in high-aspect ratio microfluidic chambers using time-lapse and intermittent fluorescent staining of nanofibrils, complemented with atmospheric scanning electron microscopy.

Paracoccus denitrificans can utilize various long-chain N-acyl homoserine lactones and sequester them in membrane vesicles.

Many gram-negative bacteria utilize N-acyl homoserine lactone (AHL) signals to communicate with each other. Once they have been released, these signals are assumed to be shared among the population in the local environment. In contrast to this canonical quorum-sensing (QS) model, recent study in Paracoccus denitrificans showed that they can traffic their signals to each other via membrane vesicles (MVs).

Membrane vesicle-mediated bacterial communication.

The classical quorum-sensing (QS) model is based on the assumption that diffusible signaling molecules accumulate in the culture medium until they reach a critical concentration upon which expression of target genes is triggered. Here we demonstrate that the hydrophobic signal N-hexadecanoyl-L-homoserine lactone, which is produced by Paracoccus sp., is released from cells by the aid of membrane vesicles (MVs).

The Pseudomonas Quinolone Signal Inhibits Biofilm Development of Streptococcus mutans.

Bacteria often thrive in natural environments through a sessile mode of growth, known as the biofilm. Biofilms are well-structured communities and their formation is tightly regulated. However, the mechanisms by which interspecies interactions alter the formation of biofilms have not yet been elucidated in detail.