Hyperactive antifreeze proteins

AFPs occur naturally in many fish, insects, plants, and other organisms, allowing them to survive sub-freezing temperatures. The proteins come in various forms, but all seem to act similarly—they bind to nascent ice crystals and inhibit the crystals' subsequent growth, which effectively reduces the freezing point of ice in the organism. The AFP that is found in the spruce budworm (sbw) seems to be hyperactive and especially effective at protecting its host in the frigid winters of the northern US and Canada. A US–Canada team led by physicist Ido Braslavsky (Ohio University) and biochemist Peter Davies (Queen's University) marked sbwAFP with green fluorescent protein and with the help of fluorescence microscopy observed how the hyperactive protein coated the basal planes of ice crystals, halting their growth out of that plane. Previously the researchers had studied fluorescently tagged fish AFP types I and III. In this confocal microscopy image, it is...