Microbial βγ-crystallins

beta gamma-Crystallins have emerged as a superfamily of structurally homologous proteins with representatives across the domains of life. A major portion of this superfamily is constituted by members from microorganisms. This superfamily has also been recognized as a novel group of Ca2+-binding proteins with huge diversity. The beta gamma domain shows variable properties in Ca2+ binding, stability and association with other domains. The various members present a series of evolutionary adaptations culminating in great diversity in properties and functions. Most of the predicted beta gamma-crystallins are yet to be characterized experimentally. In this review, we outline the distinctive features of microbial beta gamma-crystallins and their position in the beta gamma-crystallin superfamily. (C) 2014 Elsevier Ltd. All rights reserved.