An essential tryptophan residue in alkaline phosphatase from pearl oyster (Pinctada fucata).
Alkaline phosphatases are ubiquitous enzymes found in most species including the pearl oyster, Pinctada fucata, where it is presumably involved in nacreous biomineralization processes. In the present study, we have purified alkaline phosphatases from the pearl oyster and modified the tryptophan residues using N-bromosuccinimide (NBS). We show that the resulting inactivation of purified alkaline phosphatase by NBS is dependent on modification of only one of five tryptophan residues in the enzyme. Substrate protection experiments showed that the tryptophan residue was not located at the substrate-binding site but was involved in the catalytic activity.
Xie
Li-Ping
LP
Institute of Marine Biotechnology, Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing, 100084, China.
Xu
Guang-Rui
GR
Cao
Wei-Zhong
WZ
Zhang
Jin
J
Zhang
Rong-Qing
RQ
D000469:Alkaline Phosphatase / Q000737:chemistry*; D000818:Animals; D001974:Bromosuccinimide / Q000737:chemistry; D007700:Kinetics; D049911:Pinctada / Q000201:enzymology*; D013050:Spectrometry, Fluorescence; D013053:Spectrophotometry; D014364:Tryptophan / Q000737:chemistry*
D014364:Tryptophan; D000469:Alkaline Phosphatase; D001974:Bromosuccinimide