Molybdophyllysin, a toxic metalloendopeptidase from the tropical toadstool, Chlorophyllum molybdites.
A toxic protein, dubbed molybdophyllysin, was isolated from the tropical toadstool Chlorophyllum molybdites by following its lethal effect in mice. Analysis of the protein using SDS-PAGE revealed a single 23-kDa band. Sequence analysis of molybdophyllysin tryptic fragments showed that this protein is highly homologous to metalloendopeptidases (MEPs) obtained from edible mushrooms, such as Grifola frondosa, Pleurotus ostreatus, and Armillaria mellea. These proteins include a HEXXH+D zinc-binding motif known as aspzincin. Accordingly, molybdophyllysin is a member of the deuterolysin family of zinc proteases. Molybdophyllysin retained its proteolytic activity at temperatures up to 60°C with an optimum pH of 7.0. The activity was inhibited by both 1,10-phenanthroline and N-bromosuccinimide, but molybdophyllysin exhibited strong resistance to SDS.
Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Japan.
Mina
M
Yamada
Naoko
N
Tokumitsu
Yoko
Y
Saikawa
Masaya
M
Nakata
Junpei
J
Asano
Kazuo
K
Miyairi
Toshikatsu
T
Okuno
Katsuhiro
K
Konno
Kimiko
K
Hashimoto
D000363:Agaricales / Q000201:enzymology*; D000595:Amino Acid Sequence; D000818:Animals; D001974:Bromosuccinimide / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008666:Metalloendopeptidases / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D010618:Phenanthrolines / Q000737:chemistry; D017386:Sequence Homology, Amino Acid; D013696:Temperature; D015032:Zinc / Q000737:chemistry / Q000378:metabolism
D010618:Phenanthrolines; D008666:Metalloendopeptidases; C039830:peptidyl-Lys metalloendopeptidase; D015032:Zinc; D001974:Bromosuccinimide; C025205:1,10-phenanthroline