Dataset Information

Expression and Functions of CreD, an Inner Membrane Protein in Stenotrophomonas maltophilia.

ABSTRACT: CreBC is a highly conserved two-component regulatory system (TCS) in several gram-negative bacteria, including Escherichia coli, Aeromonas spp., Pseudomonas aeruginosa, and Stenotrophomonas maltophilia. CreD is a conserved gene that encodes a predicted inner-membrane protein and is located near the creBC loci. Activation of CreBC increases creD expression; therefore, creD expression is generally used as a measure of CreBC activation in E. coli, Aeromonas spp., and P. aeruginosa systems. In this article, we aim to elucidate the expression of creD and further to investigate its functions in S. maltophilia. In spite of a short intergenic region of 81 bp between creBC and creD, creD is expressed separately from the adjacent creBC operon and from a promoter immediately upstream of creD (PcreD) in S. maltophilia. We found that the promoter activity of PcreD is negatively regulated by the creBC TCS, positively regulated by the bacterial culture density, and not affected by ?-lactams. Furthermore, creD expression is not significantly altered in the presence of the phosphor-mimic variant of CreB, CreB(D55E), which mimics activated CreB. The functions of CreD of S. maltophilia were assessed by comparison among the following: wild-type KJ; the creD isogenic mutant, KJ?CreD; and the complementary strain, KJ?CreD(pCreD). The mutant lacking creD had cell division defects and aberrations in cell envelope integrity, which then triggered the ?E-mediated envelope stress response. Thus, the results indicated that CreD plays a critical role in the maintenance of envelope integrity.

SUBMITTER: Huang HH

PROVIDER: S-EPMC4689548 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Expression and Functions of CreD, an Inner Membrane Protein in Stenotrophomonas maltophilia.

Huang Hsin-Hui HH Lin Yi-Tsung YT Chen Wei-Ching WC Huang Yi-Wei YW Chen Shiang-Jiuun SJ Yang Tsuey-Ching TC

PloS one 20151223 12

CreBC is a highly conserved two-component regulatory system (TCS) in several gram-negative bacteria, including Escherichia coli, Aeromonas spp., Pseudomonas aeruginosa, and Stenotrophomonas maltophilia. CreD is a conserved gene that encodes a predicted inner-membrane protein and is located near the creBC loci. Activation of CreBC increases creD expression; therefore, creD expression is generally used as a measure of CreBC activation in E. coli, Aeromonas spp., and P. aeruginosa systems. In this ...[more]

PMID: 26698119

Similar Datasets

Project description:The CreBC two-component system (TCS) is a conserved regulatory system found in Escherichia coli, Aeromonas spp., Pseudomonas aeruginosa, and Stenotrophomonas maltophilia. In this study, we determined how CreBC TCS regulates secreted protease activities and swimming motility using creB, creC, and creBC in-frame deletion mutants (KJΔCreB, KJΔCreC, and KJΔBC) of S. maltophilia KJ. Compared to wild-type KJ, KJΔCreB had a comparable secreted protease activity; however, the secreted protease activities were obviously reduced in KJΔCreC and KJΔBC, suggesting that CreC works together with another unidentified response regulator (not CreB) to regulate secreted protease activity. Single gene inactivation of creB or creC resulted in mutants with an enhanced swimming motility, and this phenotype was exacerbated in a double mutant KJΔBC. To elucidate the underlying mechanism responsible for the ΔcreBC-mediated swimming enhancement, flagella morphology observation, RNA-seq based transcriptome assay, qRT-PCR, and membrane integrity and potential assessment were performed. Flagella morphological observation ruled out the possibility that swimming enhancement was due to altered flagella morphology. CreBC inactivation upregulated the expression of creD and flagella-associated genes encoding the basal body- and motor-associated proteins. Furthermore, KJΔBC had an increased membrane susceptibility to Triton X-100 and CreD upregulation in KJΔBC partially alleviated the compromise of membrane integrity. The impact of creBC TCS on bacterial membrane potential was assessed by carbonyl cyanide m-chlorophenyl hydrazine (CCCP50) concentration at which 50% of bacterial swimming is inhibited. CCCP50 of wild-type KJ increased when creBC was deleted, indicating an association between the higher membrane potential of KJΔBC cells and enhanced motility. Upregulation of the basal body- and motor-associated genes of flagella in KJΔBC cells may explain the increased membrane potential. Collectively, inactivation of creBC increased swimming motility through membrane potential increase and creD upregulation in S. maltophilia. The increased membrane potential may supply more energy for flagella propelling and CreD upregulation supports membrane stability, providing a strong membrane for flagellum function.

Dataset Information

Expression and Functions of CreD, an Inner Membrane Protein in Stenotrophomonas maltophilia.

Publications

Expression and Functions of CreD, an Inner Membrane Protein in Stenotrophomonas maltophilia.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets