TB Research

Decrypting the oscillating nature of the 4'-phosphopantetheine arm in acyl carrier protein AcpM of Mycobacterium tuberculosis

Biswas R, Singh BK, Dutta D, Das PK, Maiti MK, Basak A, Das AK

FEBS letters · 2019-03

Abstract

In Mycobacterium tuberculosis, acyl carrier protein (AcpM)-mediated fatty acid synthase type II is integral for the synthesis of mycolic acids. AcpM, designated as an atypical ACP, comprises of a putative 33 amino acid long C-terminal extension which is distinctive in nature. Here, we aimed at devising an 'easy-to-go' method for the generation of crypto-AcpM loaded with a solvatochromic probe 7-Nitrobenz-2-oxa-1,3-diazol-4-yl, which is linked to the 4'-phosphopantetheine (Ppant) prosthetic group of AcpM. The crypto-AcpM, coupled with fluorescence spectroscopy and molecular dynamics simulation studies, was employed to explore the elusive dynamics of Ppant arm in AcpM. This investigation establishes the role of the flexible C-terminal extension of AcpM in regulating the prosthetic group sequestration ability by modulating the 'Asp-Ser-Leu' motif.

MeSH terms

  • Escherichia coli
  • Mycobacterium tuberculosis
  • Mycolic Acids
  • Nitrobenzenes
  • Pantetheine
  • Azoles
  • Coenzyme A
  • Bacterial Proteins
  • Carrier Proteins
  • Recombinant Proteins
  • Fluorescent Dyes
  • Cloning, Molecular
  • Sequence Alignment
  • Gene Expression
  • Binding Sites
  • Amino Acid Motifs
  • Protein Binding
  • Sequence Homology, Amino Acid
  • Substrate Specificity
  • Genetic Vectors
  • Protein Interaction Domains and Motifs
  • Molecular Dynamics Simulation
  • Molecular Docking Simulation
  • Protein Conformation, alpha-Helical