title: 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.
authors.affiliation: Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA.
authors.forename: Mingchi
authors.initials: M
authors.lastname: Sun
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Li
authors.forename: Harshal A
authors.initials: HA
authors.lastname: Chokhawala
authors.forename: Ryan
authors.initials: R
authors.lastname: Henning
authors.forename: Xi
authors.initials: X
authors.lastname: Chen
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D002846:Chromatography, Affinity; D002851:Chromatography, High Pressure Liquid; D004229:Dithiothreitol / Q000494:pharmacology; D004492:Edetic Acid / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation / Q000187:drug effects; D007477:Ions / Q000494:pharmacology; D007700:Kinetics; D019158:N-Acetylneuraminic Acid / Q000378:metabolism; D010776:Photobacterium / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D011522:Protons; D012799:Sialyltransferases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D013329:Structure-Activity Relationship
chemical_list: D001426:Bacterial Proteins; D007477:Ions; D011522:Protons; D004492:Edetic Acid; D012799:Sialyltransferases; D019158:N-Acetylneuraminic Acid; D004229:Dithiothreitol