pubmed-article:8305486 | pubmed:abstractText | The squalene-hopene cyclase of the hopanoid- and tetrahymanol-producing Rhodopseudomonas palustris was released from the isolated membranes by CHAPS and purified to homogeneity by successive chromatography on DEAE Sephacel, Octyl Sepharose, and Blue Sepharose. The enzyme has a molecular weight of 70 kDa as determined by SDS-PAGE and an isoelectric point at about pH 5.0. The enzyme activity has a maximum at 30 degrees C and at pH 6.5. No production of tetrahymanol could be demonstrated by using either crude or purified cyclase preparations. | lld:pubmed |