Phosphorylation controls the functioning of Staphylococcus aureus isocitrate dehydrogenase – favours biofilm formation

Abstract

Isocitrate dehydrogenase (IDH) gene from Staphylococcus aureus ATCC12600 was cloned, sequenced and characterized (HM067707). PknB site was observed in the active site of IDH; thus, it was predicted as IDH may be regulated by phosphorylation. Therefore, in this study, PknB, alkaline phosphatase III (SAOV 2675) and IDH genes (JN695616, JN645811 and HM067707) of S. aureus ATCC12600 were over expressed from clones PV 1, UVPALP-3 and UVIDH 1. On passing the cytosloic fractions through nickel metal chelate column, pure enzymes were obtained. Phosphorylation of pure IDH by PknB resulted in the complete loss of activity and was restored upon dephosphorylation with SAOV 2675 which indicated that phosphorylation and dephosphorylation regulate IDH activity in S. aureus. Further, when S. aureus ATCC12600 was grown in BHI broth, decreased IDH activity and increased biofilm units were observed; therefore, this regulation of IDH alters redox status in this pathogen favouring biofilm formation.

• Biofilm
• dephosphorylation
• IDH
• phosphorylation
• PknB
• SAOV 2675

Declaration of interest

Authors report no conflict of interest. We sincerely acknowledge Sri Venkateswara Institute of Medical Sciences University for providing funds and facilities under SBAVP scheme (SBAVP/Ph. D/02) to carry out this work, and this paper is a part of Ph.D. work going to be submitted to SVIMS University.