Tubercle bacilli generate a novel cell wall-associated pigment after long-term anaerobic culture.
Many cases of tuberculosis result from reactivation of previously acquired latent infections. Models to study such persister forms often involve gradual depletion of oxygen during culture as poor aeration is a characteristic of non-progressive TB granulomas. Anaerobically cultured bacilli develop a thickened outer-most cell wall layer. Here, we analyzed this layer from anaerobically cultured Mycobacterium tuberculosis and Mycobacterium bovis BCG. By six weeks of anaerobiosis a pigment was detected at levels > 60-fold higher in anaerobic than aerobic bacilli. This pigment was responsible for the electron-dense appearance of the thickened cell wall layer and gave an electrospray mass spectrometry peak at 409 Da (M+Na)+ or (M+H)+. We termed this pigment APP1, anaerobically produced pigment 1, the first pigment identified in M. tuberculosis.
Cunningham
Adam F
AF
Birmingham Centre for Immune Regulation, University of Birmingham, Birmingham B15 2TT, UK. a.f.Cunningham@bham.ac.uk
Ashton
Peter R
PR
Spreadbury
Claire L
CL
Lammas
David A
DA
Craddock
Rachel
R
Wharton
Christopher W
CW
Wheeler
Paul R
PR
D000693:Anaerobiosis; D002473:Cell Wall / Q000737:chemistry / Q000648:ultrastructure; D000431:Ethanol / Q000737:chemistry; D008970:Molecular Weight; D009163:Mycobacterium bovis / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure; D009169:Mycobacterium tuberculosis / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure; D010860:Pigments, Biological / Q000032:analysis* / Q000096:biosynthesis / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization; D013997:Time Factors
D010860:Pigments, Biological; D000431:Ethanol