Premium
Ice and anti‐nucleating activities of an ice‐binding protein from the annual grass, Brachypodium distachyon
Author(s) -
Bredow Melissa,
Tomalty Heather E.,
Smith Lindsay,
Walker Virginia K.
Publication year - 2018
Publication title -
plant, cell and environment
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.646
H-Index - 200
eISSN - 1365-3040
pISSN - 0140-7791
DOI - 10.1111/pce.12889
Subject(s) - brachypodium distachyon , ice crystals , ice nucleus , brachypodium , nucleation , chemistry , crystallography , biophysics , botany , materials science , biology , astrobiology , microbiology and biotechnology , biochemistry , physics , meteorology , organic chemistry , genome , gene
Plants exposed to sub‐zero temperatures face unique challenges that threaten their survival. The growth of ice crystals in the extracellular space can cause cellular dehydration, plasma membrane rupture and eventual cell death. Additionally, some pathogenic bacteria cause tissue damage by initiating ice crystal growth at high sub‐zero temperatures through the use of ice‐nucleating proteins (INPs), presumably to access nutrients from lysed cells. An annual species of brome grass, Brachypodium distachyon ( Bd ) , produces an ice‐binding protein (IBP) that shapes ice with a modest depression of the freezing point (~0.1 °C at 1 mg/mL), but high ice‐recrystallization inhibition (IRI) activity, allowing ice crystals to remain small at near melting temperatures. This IBP, known as Bd IRI, is unlike other characterized IBPs with a single ice‐binding face, as mutational analysis indicates that Bd IRI adsorbs to ice on two faces. Bd IRI also dramatically attenuates the nucleation of ice by bacterial INPs (up to −2.26 °C). This ‘anti‐nucleating’ activity is significantly higher than previously documented for any IBP.