Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Canada.
Department of Glaciology, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany.
FEBS J. 2019 Mar;286(5):855-873. doi: 10.1111/febs.14764. Epub 2019 Feb 9.
Ice-binding proteins (IBPs) control the growth and shape of ice crystals to cope with subzero temperatures in psychrophilic and freeze-tolerant organisms. Recently, numerous proteins containing the domain of unknown function (DUF) 3494 were found to bind ice crystals and, hence, are classified as IBPs. DUF3494 IBPs constitute today the most widespread of the known IBP families. They can be found in different organisms including bacteria, yeasts and microalgae, supporting the hypothesis of horizontal transfer of its gene. Although the 3D structure is always a discontinuous β-solenoid with a triangular cross-section and an adjacent alpha-helix, DUF3494 IBPs present very diverse activities in terms of the magnitude of their thermal hysteresis and inhibition of ice recrystallization. The proteins are secreted into the environments around the host cells or are anchored on their cell membranes. This review covers several aspects of this new class of IBPs, which promise to leave their mark on several research fields including structural biology, protein biochemistry and cryobiology.
冰结合蛋白（IBPs）控制冰晶的生长和形状，以应对嗜冷和抗冻生物的低温。最近，发现许多含有未知功能域（DUF）3494 的蛋白质能与冰晶结合，因此被归类为 IBPs。DUF3494 IBP 是目前已知 IBP 家族中分布最广泛的。它们可以在不同的生物体中找到，包括细菌、酵母和微藻，这支持了其基因水平转移的假说。尽管 3D 结构始终是一个具有三角形横截面和相邻α-螺旋的不连续β-螺线管，但 DUF3494 IBP 在其热滞和抑制冰晶重结晶的幅度方面表现出非常多样化的活性。这些蛋白质被分泌到宿主细胞周围的环境中，或锚定在它们的细胞膜上。本综述涵盖了这一新类 IBPs 的几个方面，它们有望在结构生物学、蛋白质生物化学和低温生物学等几个研究领域留下自己的印记。
