NTRS - NASA Technical Reports Server

Back to Results
Sequence and Genetic Characterization of etrA, an fnr Analog that Regulates Anaerobic Respiration in Shewanella putrefaciens MR-1An electron transport regulatory gene, etrA, has been isolated and characterized from the obligate respiratory bacterium Shewanella putrefaciens MR-l. The deduced amino acid sequence of etrA (EtrA) shows a high degree of identity to both the Fnr of Escherichia coli (73.6%) and the analogous protein (ANR) of Pseudomonas aeruginosa (50.8%). The four active cysteine residues of Fnr are conserved in EtrA, and the amino acid sequence of the DNA-binding domains of the two proteins are identical. Further, S.putrefaciens etrA is able to complement an fnr mutant of E.coli. In contrast to fnr, there is no recognizable Fnr box upstream of the etrA sequence. Gene replacement etr.A mutants of MR-1 were deficient in growth on nitrite, thiosulfate, sulfite, trimethylamine-N-oxide, dimethyl sulfoxide, Fe(III), and fumarate, suggesting that EtrA is involved in the regulation of the corresponding reductase genes. However, the mutants were all positive for reduction of and growth on nitrate and Mn(IV), indicating that EtrA is not involved in the regulation of these two systems. Southern blots of S.putrefaciens DNA with use of etrA as a probe revealed the expected etrA bands and a second set of hybridization signals whose genetic and functional properties remain to be determined.
Document ID
Document Type
Reprint (Version printed in journal)
Saffarini, Daad A. (Wisconsin Univ. Milwaukee, WI United States)
Nelson, Kenneth H. (Wisconsin Univ. Milwaukee, WI United States)
Date Acquired
August 17, 2013
Publication Date
December 1, 1993
Publication Information
Publication: Journal of Bacteriology
ISSN: 0021-9193
Subject Category
Life Sciences (General)
Report/Patent Number
NAS 1.26:203747
Funding Number(s)
Distribution Limits
Public Use Permitted.
Document Inquiry