Open AccessFnrP interactions with the Pasteurella haemolytica leukotoxin promoter
Author(s) -
Uhlich Gaylen A.,
McNamara Peter J.,
Iandolo John J.,
Mosier Derek A.
Publication year - 2000
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2000.tb09084.x
Subject(s) - escherichia coli , mutant , microbiology and biotechnology , anaerobic exercise , anaerobic respiration , transcription (linguistics) , biology , pasteurella , regulator , lac operon , gene , bacteria , promoter , enterobacteriaceae , chemistry , gene expression , biochemistry , genetics , physiology , linguistics , philosophy
Pasteurella haemolytica FnrP is homologous to Fnr, the global transcriptional regulator of anaerobic respiration in Escherichia coli . To investigate the role of O 2 in the expression of P. haemolytica leukotoxin, we tested a lktC::lacZ fusion constructed in E. coli for a FnrP‐mediated regulatory effect under aerobic and anaerobic growth conditions. Both E. coli Fnr and FnrP suppressed leukotoxin transcription under aerobic conditions. Under anaerobic conditions, Fnr suppressed transcription, while FnrP increased transcription. These results were confirmed using FnrP*, a mutant form of FnrP that activates anaerobically inducible genes under aerobic conditions. In mobility shift assays, partially purified FnrP bound to a potential regulatory site in a P. haemolytica lktC promoter fragment.