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Structures of the DfsB Protein Family Suggest a Cationic, Helical Sibling Lethal Factor Peptide.

ABSTRACT: Bacteria have developed a variety of mechanisms for surviving harsh environmental conditions, nutrient stress and overpopulation. Paenibacillus dendritiformis produces a lethal protein (Slf) that is able to induce cell death in neighbouring colonies and a phenotypic switch in more distant ones. Slf is derived from the secreted precursor protein, DfsB, after proteolytic processing. Here, we present new crystal structures of DfsB homologues from a variety of bacterial species and a surprising version present in the yeast Saccharomyces cerevisiae. Adopting a four-helix bundle decorated with a further three short helices within intervening loops, DfsB belongs to a non-enzymatic class of the DinB fold. The structure suggests that the biologically active Slf fragment may possess a C-terminal helix rich in basic and aromatic residues that suggest a functional mechanism akin to that for cationic antimicrobial peptides.

SUBMITTER: Taylor JD

PROVIDER: S-EPMC4773401 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Structures of the DfsB Protein Family Suggest a Cationic, Helical Sibling Lethal Factor Peptide.

Taylor Jonathan D JD Taylor Gabrielle G Hare Stephen A SA Matthews Steve J SJ

Journal of molecular biology 20160121 3

Bacteria have developed a variety of mechanisms for surviving harsh environmental conditions, nutrient stress and overpopulation. Paenibacillus dendritiformis produces a lethal protein (Slf) that is able to induce cell death in neighbouring colonies and a phenotypic switch in more distant ones. Slf is derived from the secreted precursor protein, DfsB, after proteolytic processing. Here, we present new crystal structures of DfsB homologues from a variety of bacterial species and a surprising vers ...[more]

PMID: 26804569

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