TY  - JOUR
ID  - open1532
UR  - http://scripts.iucr.org/cgi-bin/paper?S1399004714000121
IS  - Pt 4
A1  - Shukla, Jinal
A1  - Gupta, Radhika
A1  - Thakur, Krishan Gopal
A1  - Gokhale, Rajesh
A1  - Gopal, B
Y1  - 2014/04//
N2  - The host-pathogen interactions in Mycobacterium tuberculosis infection are significantly influenced by redox stimuli and alterations in the levels of secreted antigens. The extracytoplasmic function (ECF) ? factor ?(K) governs the transcription of the serodominant antigens MPT70 and MPT83. The cellular levels of ?(K) are regulated by the membrane-associated anti-?(K) (RskA) that localizes ?(K) in an inactive complex. The crystal structure of M. tuberculosis ?(K) in complex with the cytosolic domain of RskA (RskAcyto) revealed a disulfide bridge in the -35 promoter-interaction region of ?(K). Biochemical experiments reveal that the redox potential of the disulfide-forming cysteines in ?(K) is consistent with its role as a sensor. The disulfide bond in ?(K) influences the stability of the ?(K)-RskAcyto complex but does not interfere with ?(K)-promoter DNA interactions. It is noted that these disulfide-forming cysteines are conserved across homologues, suggesting that this could be a general mechanism for redox-sensitive transcription regulation.
PB  - Malden, MA : Wiley-Blackwell
JF  - Acta crystallographica. Section D, Biological crystallography
VL  - 70
KW  - transcription; redox sensitivity; secreted antigens; extracytoplasmic function [sigma] factors.
SN  - 1399-0047
TI  - Structural basis for the redox sensitivity of the Mycobacterium tuberculosis SigK-RskA ?-anti-? complex.
SP  - 1026
EP  - 36
ER  -