Multifunctional essentiality of succinate metabolism in adaptation to hypoxia in Mycobacterium tuberculosis Academic Article uri icon

Overview

MeSH Major

  • Adaptation, Physiological
  • Citric Acid Cycle
  • Mycobacterium tuberculosis
  • Succinic Acid

abstract

  • Mycobacterium tuberculosis is a chronic, facultative intracellular pathogen that spends the majority of its decades-long life cycle in a non- or slowly replicating state. However, the bacterium remains poised to resume replicating so that it can transmit itself to a new host. Knowledge of the metabolic adaptations used to facilitate entry into and exit from nonreplicative states remains incomplete. Here, we apply (13)C-based metabolomic profiling to characterize the activity of M. tuberculosis tricarboxylic acid cycle during adaptation to and recovery from hypoxia, a physiologically relevant condition associated with nonreplication. We show that, as M. tuberculosis adapts to hypoxia, it slows and remodels its tricarboxylic acid cycle to increase production of succinate, which is used to flexibly sustain membrane potential, ATP synthesis, and anaplerosis, in response to varying degrees of O2 limitation and the presence or absence of the alternate electron acceptor nitrate. This remodeling is mediated by the bifunctional enzyme isocitrate lyase acting in a noncanonical role distinct from fatty acid catabolism. Isocitrate lyase-dependent production of succinate affords M. tuberculosis with a unique and bioenergetically efficient metabolic means of entry into and exit from hypoxia-induced quiescence.

publication date

  • April 16, 2013

Research

keywords

  • Academic Article

Identity

Language

  • eng

PubMed Central ID

  • PMC3631649

Digital Object Identifier (DOI)

  • 10.1073/pnas.1219375110

PubMed ID

  • 23576728

Additional Document Info

start page

  • 6554

end page

  • 9

volume

  • 110

number

  • 16