title: Group 3 LEA protein model peptides protect enzymes against desiccation stress.
abstract: We tested whether model peptides for group 3 late embryogenesis abundant (G3LEA) proteins, which we developed previously, are capable of maintaining the catalytic activities of enzymes dried in their presence. Three different peptides were compared: 1) PvLEA-22, which consists of two tandem repeats of the 11-mer motif found in G3LEA proteins from an African sleeping chironomid; 2) PvLEA-44, which is made of four tandem repeats of the same 11-mer motif; and 3) a peptide whose amino acid composition is the same as that of PvLEA-22, but whose sequence is scrambled. We selected two enzymes, lactate dehydrogenase (LDH) and β-d-galactosidase (BDG), as targets because they have different isoelectric point (pI) values, in the alkaline and acidic range, respectively. While these enzymes were almost inactivated when dried alone, their catalytic activity was preserved at ≥70% of native levels in the presence of any of the above three peptides. This degree of protection is comparable to that conferred by several full-length G3LEA proteins, as reported previously for LDH. Interestingly, the protective activity of the peptides was enhanced slightly when they were mixed with trehalose, especially when the molar content of the peptides was low. On the basis of these results, the G3LEA model peptides show promise as protectants for the dry preservation of enzymes/proteins with a wide range of pI values.
authors.affiliation: Center for Biological Resources and Informatics, Tokyo Institute of Technology, 4259-B-62, Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Furuki
authors.affiliation: Center for Biological Resources and Informatics, Tokyo Institute of Technology, 4259-B-62, Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan. Electronic address: msakurai@bio.titech.ac.jp.
authors.forename: Minoru
authors.initials: M
authors.lastname: Sakurai
mesh_terms: D000818:Animals; D055162:Biocatalysis; D002683:Chironomidae / Q000737:chemistry; D003890:Desiccation; D006863:Hydrogen-Ion Concentration; D019476:Insect Proteins / Q000737:chemistry*; D007526:Isoelectric Point; D007700:Kinetics; D007770:L-Lactate Dehydrogenase / Q000737:chemistry*; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry*; D010940:Plant Proteins / Q000737:chemistry*; D020011:Protective Agents / Q000737:chemistry*; D020080:Tandem Repeat Sequences; D001616:beta-Galactosidase / Q000737:chemistry*
chemical_list: D019476:Insect Proteins; D010455:Peptides; D010940:Plant Proteins; D020011:Protective Agents; C066246:late embryogenesis abundant protein, plant; D007770:L-Lactate Dehydrogenase; D001616:beta-Galactosidase
keywords: Desiccation tolerance; Dry preservation; Enzyme; Group 3 LEA protein model peptide; Trehalose