PDBsum entry 5oay

Signaling protein

PDB id: 5oay

Contents

Protein chain

76 a.a.

Ligands

SF4

PDB id:

5oay

Name:

Signaling protein

Title:

M. Tuberculosis [4fe-4s] protein whib1 is a four-helix bundle that forms a no-sensitive complex with sigmaa and regulates the major virulence factor esx-1

Structure:

Transcriptional regulator whib1. Chain: a. Engineered: yes. Other_details: the sequence provided begins 9 residues before the start of the folded protein

Source:

Mycobacterium tuberculosis (strain atcc 25618 / h37rv). Organism_taxid: 83332. Gene: whib1, rv3219. Expressed in: mycobacterium smegmatis. Expression_system_taxid: 1772

NMR struc:

10 models

Authors:

M.P.Williamson,J.Green,A.M.Hounslow

Key ref:

B.K.Kudhair et al. (2017). Structure of a Wbl protein and implications for NO sensing by M. tuberculosis. Nat Commun, 8, 2280. PubMed id: 29273788

Date:

25-Jun-17 Release date: 03-Jan-18

Protein chain

P9WF43  (WHIB1_MYCTU) -  Transcriptional regulator WhiB1 from Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv)

Seq: 84 a.a.

Struc: 76 a.a.

Enzyme reactions

• Enzyme class: E.C.?

Nat Commun 8:2280 (2017)

PubMed id: 29273788

Structure of a Wbl protein and implications for NO sensing by M. tuberculosis.

B.K.Kudhair, A.M.Hounslow, M.D.Rolfe, J.C.Crack, D.M.Hunt, R.S.Buxton, L.J.Smith, N.E.Le Brun, M.P.Williamson, J.Green.

ABSTRACT

Mycobacterium tuberculosis causes pulmonary tuberculosis (TB) and claims ~1.8 million human lives per annum. Host nitric oxide (NO) is important in controlling TB infection. M. tuberculosis WhiB1 is a NO-responsive Wbl protein (actinobacterial iron-sulfur proteins first identified in the 1970s). Until now, the structure of a Wbl protein has not been available. Here a NMR structural model of WhiB1 reveals that Wbl proteins are four-helix bundles with a core of three α-helices held together by a [4Fe-4S] cluster. The iron-sulfur cluster is required for formation of a complex with the major sigma factor (σ^A) and reaction with NO disassembles this complex. The WhiB1 structure suggests that loss of the iron-sulfur cluster (by nitrosylation) permits positively charged residues in the C-terminal helix to engage in DNA binding, triggering a major reprogramming of gene expression that includes components of the virulence-critical ESX-1 secretion system.