| First Author | Abe I | Year | 2001 |
| Journal | Biochim Biophys Acta | Volume | 1522 |
| Issue | 2 | Pages | 67-73 |
| PubMed ID | 11750056 | Mgi Jnum | J:73376 |
| Mgi Id | MGI:2155022 | Doi | 10.1016/s0167-4781(01)00307-4 |
| Citation | Abe I, et al. (2001) Molecular cloning, expression, and site-directed mutations of oxidosqualene cyclase from Cephalosporium caerulens(1). Biochim Biophys Acta 1522(2):67-73 |
| abstractText | A cDNA for oxidosqualene:lanosterol cyclase (OSLC) was cloned and sequenced from the fungus Cephalosporium caerulens, that produces a steroidal antibiotic, helvolic acid. A 2280 bp open reading frame encoded an M(r) 87078 protein with 760 amino acids. The cDNA was functionally expressed in the OSLC-deficient mutant GIL77 strain of Saccharomyces cerevisiae. A truncated recombinant enzyme (Delta49N) starting from the second methionine (M50) residue was completely inactive, suggesting that ca. 30 additional hydrophilic amino acid residues at the N-terminal are essential for the folding of the enzyme. Furthermore, the active site residues, H234 and D456 (numbering in S. cerevisiae OSLC), were chosen for site-directed mutagenesis experiments; H234E, H234Y, H234F, D456E, D456N, and D456H mutants were inactive, while H234W and H234K mutants retained lanosterol-forming activity. |
