Membranes Are Decisive for Maximum Freezing Efficiency of Bacterial Ice Nucleators.

ABSTRACT: Ice-nucleating proteins (INPs) from Pseudomonas syringae are among the most active ice nucleators known, enabling ice formation at temperatures close to the melting point of water. The working mechanisms of INPs remain elusive, but their ice nucleation activity has been proposed to depend on the ability to form large INP aggregates. Here, we provide experimental evidence that INPs alone are not sufficient to achieve maximum freezing efficiency and that intact membranes are critical. Ice nucleation measurements of phospholipids and lipopolysaccharides show that these membrane components are not part of the active nucleation site but rather enable INP assembly. Substantially improved ice nucleation by INP assemblies is observed for deuterated water, indicating stabilization of assembl

SUBMITTER: Schwidetzky R 

PROVIDER: S-EPMC8591660 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature