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N-Terminal 112 amino acid residues are not required for the sialyltransferase activity of Photobacterium damsela alpha2,6-sialyltransferase.

ABSTRACT: Photobacterium damsela alpha2,6-sialyltransferase was cloned as N- and C- His-tagged fusion proteins with different lengths (16-497 aa or 113-497 aa). Expression and activity assays indicated that the N-terminal 112 amino acid residues of the protein were not required for its alpha2,6-sialyltransferase activity. Among four truncated forms tested, N-His-tagged Delta15Pd2,6ST(N) containing 16-497 amino acid residues had the highest expression level. Similar to the Delta15Pd2,6ST(N), the shorter Delta112Pd2,6ST(N) was active in a wide pH range of 7.5-10.0. A divalent metal ion was not required for the sialyltransferase activity, and the addition of EDTA and dithiothreitol did not affect the activity significantly.

SUBMITTER: Sun M

PROVIDER: S-EPMC2598773 | biostudies-literature | 2008 Apr

REPOSITORIES: biostudies-literature

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N-Terminal 112 amino acid residues are not required for the sialyltransferase activity of Photobacterium damsela alpha2,6-sialyltransferase.

Sun Mingchi M Li Yanhong Y Chokhawala Harshal A HA Henning Ryan R Chen Xi X

Biotechnology letters 20071108 4

Photobacterium damsela alpha2,6-sialyltransferase was cloned as N- and C- His-tagged fusion proteins with different lengths (16-497 aa or 113-497 aa). Expression and activity assays indicated that the N-terminal 112 amino acid residues of the protein were not required for its alpha2,6-sialyltransferase activity. Among four truncated forms tested, N-His-tagged Delta15Pd2,6ST(N) containing 16-497 amino acid residues had the highest expression level. Similar to the Delta15Pd2,6ST(N), the shorter De ...[more]

PMID: 17989925

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