title: Aspartyl aminopeptidase of Schizosaccharomyces pombe has a molecular chaperone function.
abstract: To screen chaperone proteins from Schizosaccharomyce pombe (S. pombe), we prepared recombinant citrate synthase of the fission yeast as a substrate of anti-aggregation assay. Purified recombinant citrate synthase showed citrate synthase activity and was suitable for the substrate of chaperone assay. Several heat stable proteins including aspartyl aminopeptidase (AAP) for candidates of chaperone were screened from the supernatant fraction of heat-treated crude extract of S. pombe. The purified AAP migrated as a single band of 47 kDa on SDS-polyacrylamide gel electrophoresis. The native size of AAP was estimated as 200 kDa by a HPLC gel permeation chromatography. This enzyme can remove the aspartyl residue at N-terminus of angiotensin I. In addition, AAP showed the heat stability and protected the aggregation of citrate synthase caused by thermal denaturation. This study showed that S. pombe AAP is a moonlight protein that has aspartyl aminopeptidase and chaperone activities.
authors.affiliation: School of Biological Sciences and Technology, Chonnam National University, Gwangju, Korea.
authors.forename: Songmi
authors.initials: S
authors.lastname: Lee
authors.forename: Ji Sun
authors.initials: JS
authors.lastname: Kim
authors.forename: Chul Ho
authors.initials: CH
authors.lastname: Yun
authors.forename: Ho Zoon
authors.initials: HZ
authors.lastname: Chae
authors.forename: Kanghwa
authors.initials: K
authors.lastname: Kim
mesh_terms: D000626:Aminopeptidases / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D004789:Enzyme Activation; D004795:Enzyme Stability; D006358:Hot Temperature; D018832:Molecular Chaperones / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D012568:Schizosaccharomyces / Q000201:enzymology* / Q000378:metabolism; D013997:Time Factors
chemical_list: D018832:Molecular Chaperones; D011994:Recombinant Proteins; D029701:Saccharomyces cerevisiae Proteins; D000626:Aminopeptidases; C507984:aspartyl aminopeptidase, S cerevisiae