Cell shape and division septa positioning in filamentous require a functional cell wall glycopolymer ligase CglA.

The cell wall of monoderm bacteria consists of peptidoglycan and glycopolymers in roughly equal proportions and is crucial for cellular integrity, cell shape, and bacterial vitality. Despite the immense value of in biotechnology and medicine as antibiotic producers, we know very little about their cell wall biogenesis, composition, and functions. Here, we have identified the LCP-LytR_C domain protein CglA (Vnz_13690) as a key glycopolymer ligase which specifically localizes in zones of cell wall biosynthesis in .

Allosteric regulation of glycogen breakdown by the second messenger cyclic di-GMP.

Streptomyces are our principal source of antibiotics, which they generate concomitant with a complex developmental transition from vegetative hyphae to spores. c-di-GMP acts as a linchpin in this transition by binding and regulating the key developmental regulators, BldD and WhiG. Here we show that c-di-GMP also binds the glycogen-debranching-enzyme, GlgX, uncovering a direct link between c-di-GMP and glycogen metabolism in bacteria.

Assessment of Diadenylate Cyclase and c-di-AMP-phosphodiesterase Activities Using Thin-layer and Ion Exchange Chromatography.

All living cells use cyclic nucleotides as second messengers for signal sensing and transduction. Cyclic di-3',5'-adenosine monophosphate (c-di-AMP) is primarily involved in the control of bacterial and euryarcheal osmoadaptation and is produced by diadenylate cyclases from two molecules of ATP. Specific phosphodiesterases hydrolyze c-di-AMP to the linear phosphoadenylate adenosine 5'-pApA or to AMP.

c-di-AMP hydrolysis by the phosphodiesterase AtaC promotes differentiation of multicellular bacteria.

Antibiotic-producing use the diadenylate cyclase DisA to synthesize the nucleotide second messenger c-di-AMP, but the mechanism for terminating c-di-AMP signaling and the proteins that bind the molecule to effect signal transduction are unknown. Here, we identify the AtaC protein as a c-di-AMP-specific phosphodiesterase that is also conserved in pathogens such as and AtaC is monomeric in solution and binds Mn to specifically hydrolyze c-di-AMP to AMP via the intermediate 5'-pApA. As an effector of c-di-AMP signaling, we characterize the RCK_C domain protein CpeA.

Nucleotide second messengers in .

Antibiotic producing sense and respond to environmental signals by using nucleotide second messengers, including (p)ppGpp, cAMP, c-di-GMP and c-di-AMP. As summarized in this review, these molecules are important message carriers that coordinate the complex morphological transition from filamentous growth to sporulation along with the secondary metabolite production. Here, we provide an overview of the enzymes that make and break these second messengers and suggest candidates for (p)ppGpp and cAMP enzymes to be studied.

CagY Is an Immune-Sensitive Regulator of the Helicobacter pylori Type IV Secretion System.

Background & Aims: Peptic ulcer disease and gastric cancer are caused most often by Helicobacter pylori strains that harbor the cag pathogenicity island, which encodes a type IV secretion system (T4SS) that injects the CagA oncoprotein into host cells. cagY is an essential gene in the T4SS and has an unusual DNA repeat structure that predicts in-frame insertions and deletions. These cagY recombination events typically lead to a reduction in T4SS function in mouse and primate models.