Preliminary X-ray crystallographic analysis of thermolysin in the presence of 4 M NaCl.
The activity of thermolysin (EC 3.4.24.27) is greatly enhanced by high concentrations of neutral salts. For instance, 4 M NaCl enhances the activity 13-15-fold [Holmquist & Vallee (1976), Biochemistry, 15, 101-107; Inouye (1992), J. Biochem. (Tokyo), 112, 335-340]. To clarify the structural basis of the activation of thermolysin by high concentrations of NaCl, we have developed a new method to introduce 4 M NaCl into the P6(1)22 crystal of thermolysin originally grown without NaCl. The crystal obtained by this method diffracted X-rays to 2.43 A. No unit-cell parameter change was observed except the length of the c axis, which was elongated by 9.6% by the introduction of 4 M NaCl.
Kamo
Masayuki
M
Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
Inouye
Kuniyo
K
Nagata
Koji
K
Tanokura
Masaru
M
D001407:Bacillus / Q000201:enzymology*; D018360:Crystallography, X-Ray; D017434:Protein Structure, Tertiary; D012965:Sodium Chloride / Q000737:chemistry*; D013820:Thermolysin / Q000737:chemistry*
D012965:Sodium Chloride; D013820:Thermolysin