Chaperone activity of large-size subunit catalases.

Free radical biology & medicine (2020-06-06)
Teresa Nava-Ramírez, Wilhelm Hansberg
ABSTRACT

Large-size subunit catalases (LSCs) have a C-terminal domain that is structurally similar to DJ-1 and Hsp31 proteins, which have well documented molecular chaperone activity. Like chaperones, LSCs are abundant proteins that are induced under stress conditions and during cell differentiation in different microorganisms. Here we document that the C-terminal domain of LSCs assist other proteins to preserve their active conformation. Heat, urea, or H2O2 denaturation of alcohol dehydrogenase was prevented by LSCs or the C-terminal domain of Catalase-3 (TDC3); in contrast, small-size subunit catalases (SSCs) or LSCs without the C-terminal domain (C3ΔTD or C63) did not have this effect. Similar results were obtained if the alcohol dehydrogenase was previously denatured by heat and then the different catalases or truncated enzymes were added. The TDC3 also protected both the C3ΔTD and the bovine liver catalase from heat denaturation. The chaperone activity of CAT-3 or the TDC3 increased survival of E. coli under different stress conditions whereas the C3ΔTD did not. It is concluded that the C-terminal domain of LSCs has a chaperone activity that is instrumental for cellular resistance to stress conditions, such as oxidative stress that leads to cell differentiation in filamentous fungi.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
LB Broth (Lennox), Highly-referenced microbial growth powder medium, low salt, suitable for salt-sensitive E.coli culture.
Sigma-Aldrich
Protease from Bacillus licheniformis, Type VIII, lyophilized powder, 7-15 units/mg solid
Sigma-Aldrich
Bovine Serum Albumin, lyophilized powder, essentially globulin free, ≥99% (agarose gel electrophoresis)
Sigma-Aldrich
β-Galactosidase from Escherichia coli, lyophilized powder, ≥500 units/mg protein