Structural Bioinformatic Approach to Understand the Molecular Mechanism of the Interactions of Small Heat Shock Proteins IbpA and IbpB with Lon Protease
In order to survive under temperature stress conditions, bacterial cells come up with different biochemical mechanisms like production of chaperones; a class of proteins that maintain the proper folding of the other necessary proteins for survival. Chaperones mostly function as complexes. A member of such a family in E.coli is IbpAB protein complex. This protein complex is known to bind a protease called Lon. However, till date the modes of binding between these proteins are still obscure. In the present work, we employed molecular modeling and simulation techniques to analyze the pattern of interactions between these proteins. We observed that under cold and heat shock conditions, the interactions between IbpA and IbpB proteins increase whereas at physiological temperature the interactions decrease which allows Lon to promote better binding and degradation at physiological temperature. So far this is the first report to predict the interactions scheme between these proteins.
KeywordsIbpA-IbpB interaction Lon protease Small heat-shock protein Heat stress
The authors would like to thank the BIF center at the Department of Biochemistry and Biophysics and the DST Purse program, 2012–2015, for providing the infrastructural support. SB is thankful to DBT (Grant no: BT/PR6869/BID/7/714/2012) for financial support.
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