Transcriptome profiling of degU expression reveals unexpected regulatory patterns in Bacillus megaterium and discloses new targets for optimizing expression

Appl Microbiol Biotechnol. 2011 Nov;92(3):583-96. doi: 10.1007/s00253-011-3575-x. Epub 2011 Sep 21.

Abstract

The first whole transcriptome assessment of a Bacillus megaterium strain provides unanticipated insights into the degSU regulon considered to be of central importance for exo-enzyme production. Regulatory patterns as well as the transcription of degSU itself deviate from the model organism Bacillus subtilis; the number of DegU-regulated secretory enzymes is rather small. Targets for productivity optimization, besides degSU itself, arise from the unexpected DegU-dependent induction of the transition-state regulator AbrB during exponential growth. Induction of secretion-assisting factors, such as the translocase subunit SecY or the signal peptidase SipM, promote hypersecretion. B. megaterium DegSU transcriptional control is advantageous for production purposes, since the degU32 constitutively active mutant conferred hypersecretion of a heterologous Bacillus amyloliquefaciens amylase without the detrimental rise, as for B. subtilis and Bacillus licheniformis, in extracellular proteolytic activities.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacillus megaterium / genetics*
  • Bacillus megaterium / physiology
  • Bacterial Proteins / biosynthesis*
  • Bacterial Proteins / genetics
  • Gene Expression Profiling*
  • Gene Expression Regulation, Bacterial*
  • Transcription, Genetic

Substances

  • Bacterial Proteins
  • DegU protein, Bacteria