title: Peptidyl-prolyl cis/trans isomerase-independent functional NifH mutant of Azotobacter vinelandii.
abstract: Peptidyl-prolyl cis/trans isomerases (PPIases) play a pivotal role in catalyzing the correct folding of many prokaryotic and eukaryotic proteins that are implicated in a variety of biological functions, ranging from cell cycle regulation to bacterial infection. The nif accessory protein NifM, which is essential for the biogenesis of a functional NifH component of nitrogenase, is a PPIase. To understand the nature of the molecular signature that defines the NifM dependence of NifH, we screened a library of nifH mutants in the nitrogen-fixing bacterium Azotobacter vinelandii for mutants that acquired NifM independence. Here, we report that NifH can acquire NifM independence when the conserved Pro258 located in the C-terminal region of NifH, which wraps around the other subunit in the NifH dimer, is replaced by serine.
authors.affiliation: Department of Biological Sciences, P.O. Box GY, Mississippi State University, Mississippi State, MS 39762, USA. gavini@biology.msstate.edu
authors.forename: Nara
authors.initials: N
authors.lastname: Gavini
authors.forename: Sudheer
authors.initials: S
authors.lastname: Tungtur
authors.forename: Lakshmi
authors.initials: L
authors.lastname: Pulakat
mesh_terms: D000595:Amino Acid Sequence; D016948:Azotobacter vinelandii / Q000201:enzymology* / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D015971:Gene Expression Regulation, Enzymologic; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D010088:Oxidoreductases / Q000235:genetics* / Q000378:metabolism*; D019696:Peptidylprolyl Isomerase / Q000378:metabolism*; D011487:Protein Conformation
chemical_list: D010088:Oxidoreductases; C029130:nitrogenase reductase; D019696:Peptidylprolyl Isomerase