Original scientific paper

https://doi.org/10.5562/cca2168

Influence of Subunit Interface Mutations on Kinetic and Dynamic Properties of Alkaline Phosphatase from E. coli

Matilda Šprung orcid.org/0000-0001-5008-2700 ; Department of Chemistry, Faculty of Science, University of Split, N. Tesle 12, HR-21000 Split, Croatia
Viljemka Bučević-Popović orcid.org/0000-0001-9927-1107 ; Department of Chemistry, Faculty of Science, University of Split, N. Tesle 12, HR-21000 Split, Croatia
Barbara Soldo ; Department of Chemistry, Faculty of Science, University of Split, N. Tesle 12, HR-21000 Split, Croatia
Maja Pavela-Vrančić ; Department of Chemistry, Faculty of Science, University of Split, N. Tesle 12, HR-21000 Split, Croatia
Stjepan Orhanović orcid.org/0000-0001-8327-037X ; Department of Chemistry, Faculty of Science, University of Split, N. Tesle 12, HR-21000 Split, Croatia

Abstract

Mutations, replacing amino acids involved in the formation of hydrogen bonds between subunits
of dimeric alkaline phosphatase, have been introduced. Influence of mutations on kinetic properties and
structural stability of mutant enzymes was established. In addition, alterations in protein dynamic properties
have been studied using room temperature phosphorescence. Kinetic properties of both mutant enzymes
were virtually the same, differing from the wild type enzyme in the kcat value that was almost twice
lower. Changes in protein dynamic properties of mutant proteins, compared to the wild type enzyme, did
not parallel changes in kinetic properties suggesting that an alteration in the rigidity of the Trp109 environment
is not responsible for the reduction of kinetic properties. Instead, combined kinetic and dynamic
consequences of introduced mutations suggest that breaking of specific links, involved in transmission of
conformational change, could be responsible for altered kinetic properties. (doi: 10.5562/cca2168)

Keywords

room temperature phosphorescence; acrylamide quenching; kinetic properties; protein dynamics; subunit interface

Hrčak ID:

105564

URI

https://hrcak.srce.hr/105564

Publication date:

1.7.2013.

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