Open AccessCloning, expression and characterization of an extracellular enolase from Leuconostoc mesenteroides
Author(s) -
Lee JinHa,
Kang HeeKyoung,
Moon YoungHwan,
Cho Dong Lyun,
Kim Doman,
Choe JunYong,
Honzatko R.,
Robyt John F.
Publication year - 2006
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2006.00274.x
Subject(s) - enolase , leuconostoc mesenteroides , dextransucrase , extracellular , biochemistry , recombinant dna , biology , microbiology and biotechnology , protein subunit , escherichia coli , isozyme , chemistry , enzyme , bacteria , lactic acid , gene , immunology , genetics , immunohistochemistry
Enolase on the surface of streptococci putatively facilitates pathogenic invasion of the host organisms. The related Leuconostoc mesenteroides 512FMCM is nonpathogenic, but it too has an extracellular enolase. Purified isolates of extracellular dextransucrase from cultures of L. mesenteroides contain minute amounts of enolase, which separate as small crystals. Expression of L. mesenteroides enolase in Escherichia coli provides a protein (calculated subunit mass of 47 546 Da) catalyzing the conversion of 2‐phsopho‐ d ‐glycerate to phosphoenolpyruvate. The pH optimum is 6.8, with K m and k cat values of 2.61 mM and 27.5 s −1 , respectively. At phosphate concentrations of 1 mM and below, fluoride is a noncompetitive inhibitor with respect to 2‐phospho‐ d ‐glycerate, but in the presence of 20 mM phosphate, fluoride becomes a competitive inhibitor. Recombinant enolase significantly inhibits the activity of purified dextransucrase, and does not bind human plasminogen. Results here suggest that in some organisms enolase may participate in protein interactions that have no direct relevance to pathogenic invasion.