The βγ-Crystallin domain of Lysinibacillus sphaericus phosphatidylinositol phospholipase C plays a central role in protein stability

SEBASTIAN CERMINATI; LUCIANA PAOLETTI; SALVADOR PEIRU; HUGO G. MENZELLA; MARIA CASTELLI

APPLIED MICROBIOLOGY AND BIOTECHNOLOGY

SPRINGER

Lugar: Berlin; Año: 2018 vol. 102 p. 6997 - 7005

0175-7598

-crystallin has emerged as a superfamily of structurally homologous proteins with representatives across all the domains of life. A major portion of this superfamily isconstituted by microbial members. This superfamily has also been recognized as anovel group of Ca2+ -binding proteins with large diversity and variable properties in Ca2+ binding and stability.We have recently described a new phosphatidylinositol phospholipase C fromLysinobacillus sphaericus (LS-PIPLC) which was shown to efficiently removephosphatidylinositol from crude vegetable oil. Here, the role of the C-terminal βγ- crystallin domain of LS-PIPLC is analyzed in the context of the whole protein. Atruncated protein in which the C-terminal -crystallin domain was deleted (LSPIPLCCRY) is catalytically as efficient as the full length protein (LS-PIPLC).However, the thermal and chemical stability of LS-PIPLCCRY are highly affected,demonstrating a stabilizing role for this domain. It is also shown that the presence of Ca2+ increases the thermal and chemical stability of the protein both in aqueous media and in oil, making LS-PIPLC an excellent candidate to be used in industrial soybean oil degumming.