COMMON FEATURES OF THE NAD-BINDING AND CATALYTIC SITE OF ADP-RIBOSYLATING TOXINS

被引：90

作者：

DOMENIGHINI, M ^{[1
]}

MAGAGNOLI, C ^{[1
]}

PIZZA, M ^{[1
]}

RAPPUOLI, R ^{[1
]}

机构：

[1] IMMUNOBIOL RES INST SIENA, I-53100 SIENA, ITALY

来源：

MOLECULAR MICROBIOLOGY | 1994年 / 14卷 / 01期

关键词：

D O I：

10.1111/j.1365-2958.1994.tb01265.x

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Computer analysis of the three-dimensional structure of ADP-ribosylating toxins showed that in all toxins the NAD-binding site is located in a cavity. This cavity consists of 18 contiguous amino acids that form an alpha-helix bent over a beta-strand. The tertiary folding of this structure is strictly conserved despite the differences in the amino acid sequence. Catalysis is supported by two spatially conserved amino acids, each flanking the NAD-binding site. These are: a glutamic acid that is conserved in all toxins, and a nucleophilic residue, which is a histidine in the diphtheria toxin and Pseudomonas exotoxin A, and an arginine in the cholera toxin, the Escherichia coli heat-labile enterotoxins, the pertussis toxin and the mosquitocidal toxin of Bacillus sphaericus. The latter group of toxins presents an additional histidine that appears important for catalysis. This structure suggests a general mechanism of ADP-ribosylation evolved to work on different target proteins.

引用

页码：41 / 50

页数：10

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[1] STRUCTURE OF EXOTOXIN-A OF PSEUDOMONAS-AERUGINOSA AT 3.0-ANGSTROM RESOLUTION [J].