Substrate Specificity of Aqualysin I Altered by an Organic Solvent, DMSO.
نویسندگان
چکیده
Aqualysin I is the alkaline serine protease isolated from an extreme thermophile, Thermus aquaticus YT-1. We have analyzed the kinetic properties of aqualysin I, using thirty-one kinds of chromogenic succinyl-tripeptide p-nitroanilides as substrates in the presence of 10% dimethylsulfoxide (DMSO). Aqualysin I hydrolyzed many peptides in a DMSO-containing mixture, however the substrate specificity was different from that in the absence of DMSO. The Km for each peptide was raised by the addition of 10% DMSO. Also, the P3- as well as P2-specificity of aqualysin I was altered. These results suggested that the side chains of the P2 and P3 residues are exposed to the solvent, and the hydrophobic interactions between the side chain of the substrate and the solvent may take a part in the substrate recognition of the enzyme.
منابع مشابه
Substrate Specificity of Aqualysin I, a Bacterial Thermophilic Alkaline Serine Protease from Thermus aquaticus YT-1: Comparison with Proteinase K, Subtilisin BPN' and Subtilisin Carlsberg.
Aqualysin I is the alkaline serine protease isolated from an extreme thermophile, Thermus aquaticus YT-1. We analyzed kinetic properties of aqualysin I, using sixteen kinds of chromogenic succinyl-tripeptide p-nitroanilides as substrates. And we compared the substrate specificity of aqualysin I with those of proteinase K, subtilisin BPN', and subtilisin Carlsberg. We found that aqualysin I had ...
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ورودعنوان ژورنال:
- Bioscience, biotechnology, and biochemistry
دوره 63 2 شماره
صفحات -
تاریخ انتشار 1999