Immunity proteins: enzyme inhibitors that avoid the active site

Kleanthous, C. and Walker, D. (2001) Immunity proteins: enzyme inhibitors that avoid the active site. Trends in Biochemical Sciences, 26(10), pp. 624-631. (doi: 10.1016/S0968-0004(01)01941-7) (PMID:11590016)

Abstract

Immunity proteins are high affinity inhibitors of colicins – SOS-induced toxins released by bacteria during times of stress. Recent work has shown that nuclease-specific immunity proteins are exosite inhibitors, binding adjacent to the enzyme active site and inhibiting colicin activity indirectly. Unusually, their binding sites comprise a near contiguous sequence that lies N-terminal to active site sequences, raising the possibility that immunity proteins bind colicins co-translationally. Exosite binding accounts for the extensive sequence diversity seen at the interfaces of colicin–immunity protein complexes, which is not only a selective advantage to colicin-producing bacteria, but also represents a powerful model system for studying specificity in protein–protein recognition.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Walker, Professor Daniel
• Authors: Kleanthous, C., and Walker, D.
• College/School: College of Medical Veterinary and Life Sciences > School of Infection & Immunity
• Journal Name: Trends in Biochemical Sciences
• Publisher: Elsevier (Cell Press)
• ISSN: 0968-0004
• ISSN (Online): 1362-4326