Title:Identification of Binding Partners of CsaA - An Archaeal Chaperonic Protein of Picrophilus torridus
Volume: 28
Issue: 6
Author(s): Neelja Singhal, Archana Sharma, Manisha Aswal, Nirpendra Singh, Manish Kumar and Manisha Goel*
Affiliation:
- Department of Biophysics, University of Delhi South Campus, New Delhi 110021,India
Keywords:
Chaperone, protein-protein interactions, binding partners, liquid chromatography mass spectrometry, CsaA,
P. torridus.
Abstract:
Background: CsaA is among the few chaperones which are present in both bacteria and
archaea, but absent in eukaryotes. There are no reports on interactome analysis of CsaA from
archaea, till date. Identification of binding partners of CsaA might be helpful in understanding
CsaA-associated processes in Picrophilus torridus an extreme thermoacidophilic euryarchaeon.
Objectives: The present study was conducted to identify the binding partners of CsaA of P. torridus
(PtCsaA).
Methods: The binding partners of PtCsaA were isolated and identified using a pull down assay and
liquid chromatography-mass spectrometry (LC-MS).
Results: The results revealed twelve potential binding partners of CsaA. These were thermosome
subunits (Q6KZS2 and Q6L132), nascent polypeptide-associated complex protein (Q6L1N3), elongation
factor 1-alpha (Q6L202), uncharacterized protein (Q6L0Y6), citrate synthase (Q6L0M8), asparaginyl-
tRNA synthetase (Q6L0M5), succinyl-CoA synthetase beta chain (Q6L0B4), pyruvate
ferredoxin oxidoreductase alpha and beta chain proteins (Q6KZA7 and Q6KZA6, respectively),
malate dehydrogenase (Q6L0C3) and reversed fumarylacetoacetase (Q6KZ97). Functional categorization
revealed that of these, six proteins were involved in energy metabolic pathways, three were
archaeal chaperones, two were involved in translation and one might be a transcription regulator.
STRING-based analysis of the protein-protein interactions of the experimental interactome revealed
strong interactions among them.
Conclusion: PtCsaA might be a multifaceted protein which besides translation might also play important
role in metabolic processes of P. torridus. However, further experiments investigating the
binding partners of CsaA in other archaea are required for a better understanding of CsaA-associated
processes in archaea.
