Molecular analysis of an operon in Bacillus subtilis encoding a novel ABC transporter with a role in exoprotein production, sporulation and competence

Microbiology (Reading). 1996 Jan:142 ( Pt 1):71-77. doi: 10.1099/13500872-142-1-71.

Abstract

The levels of exoamylase and other exoenzymes of Bacillus subtilis are pleiotropically decreased by the ecs-26 (prs-26) and ecs-13 (prs-13) mutations. These mutations also cause a competence- and sporulation-deficient phenotype. In the present work, the ecs locus, which has been defined by the ecs-26 and ecs-13 mutations, was cloned and sequenced. Sequence analysis revealed a putative operon of three ORFs (ecsA, ecsB and ecsC). ecsA can encode a putative polypeptide of 248 amino acid residues containing an ATP-binding site. The polypeptide shows about 30% sequence similarity with the ATP-binding components of numerous membrane transporters of the ABC-type (ATP-binding cassette transporters or traffic ATPases). The ecs-26 mutation was found to result from a transition of one base pair chaning the glycine164 of EcsA to a glutamic acid residue in the vicinity of the putative ATP-binding pocket. ecsB was predicted to encode a hydrophobic protein with six membrane-spanning helices in a pattern found in other hydrophobic components of ABC transporters. The properties deduced for the ecsA and ecsB gene products are consistent with the interpretation that ecs encodes a novel ABC-type membrane transporter of B. subtilis. The third ORF, ecsC, can encode a putative polypeptide of 237 amino acid residues. The polypeptide does not resemble components of ABC transporters.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP-Binding Cassette Transporters / genetics*
  • ATP-Binding Cassette Transporters / metabolism
  • Amino Acid Sequence
  • Bacillus subtilis / genetics*
  • Bacillus subtilis / physiology*
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Base Sequence
  • Biological Transport
  • Cloning, Molecular
  • Molecular Sequence Data
  • Protein Structure, Secondary
  • Restriction Mapping
  • Sequence Analysis, DNA
  • Sequence Homology, Amino Acid
  • Spores, Bacterial / physiology
  • Transformation, Genetic

Substances

  • ATP-Binding Cassette Transporters
  • Bacterial Proteins
  • EcsA protein, Bacillus subtilis
  • EcsB protein, Bacillus subtilis
  • EcsC protein, Bacillus subtilis

Associated data

  • GENBANK/X87807
  • GENBANK/Y14077