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The LEA-like protein previously isolated from a homogenate of pea (Pisum sativumL.) embryonic axes heated at 80°C for 10 min (Russouwet al., 1995) was purified without exposure to heat. Peptides produced by trypsin digestion were separated by HPLC and sequenced. The protein was identified as a member of the LEA group I family. The conformation of the protein was compared before and after heat treatment by antibody affinity, circular dichroism spectroscopy, fluorescence spectroscopy and 8-anilino-1-naphthalenesulfonic acid binding. No differences could be detected, demonstrating that the protein was not irreversibly denatured by exposure to high temperature.

An LEA-like protein has been isolated and characterized from pea (Pisum sativum) embryos. It is the most prevalent protein in a homogenate of pea axes heated for 10 min at 80°C and then centifuged for 10 min at 17000g(80°C supernatant fraction). It has a molecular mass of 11 kDa and is very rich in hydrophilic amino acids, notably aspartate, glutamate and glycine. The protein is not recognized by an antibody to the group II dehydrin C-terminal consensus sequence. Antibodies to the isolated protein recognize a number of larger proteins in the 80°C supernatant fraction of pea and other legumes (chick pea, soybean and bean) as well as gramineous seeds (wheat, maize and barley). The protein undergoes a substantial increase in α-helical content at high ionic strength but does not dimerize.