Open AccessStructural diversity of the triterpenic hydrocarbons from the bacterium Zymomonas mobilis : the signature of defective squalene cyclization by the squalene/hopene cyclase
Author(s) -
Douka Eugenia,
Koukkou AnnaIrini,
Drainas Constantin,
GrosdemangeBilliard Catherine,
Rohmer Michel
Publication year - 2001
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2001.tb10682.x
Subject(s) - zymomonas mobilis , squalene , chemistry , cyclase , rhodospirillaceae , bacteria , methanol , biochemistry , stereochemistry , organic chemistry , enzyme , biology , ethanol fuel , fermentation , genetics
Twelve polycyclic triterpenic hydrocarbons (α‐ and γ‐polypodatetraenes, dammara‐20(21),24‐diene, 17‐isodammara‐12,24‐diene, eupha‐7,24‐diene, hop‐17(21)‐ene, neohop‐13(18)‐ene, 17‐isodammara‐20(21),24‐diene, neohop‐12‐ene, fern‐8‐ene, diploptene and hop‐21‐ene) were detected in the hydrocarbon fraction from the bacterium Zymomonas mobilis . Some of them have never been reported from bacteria. These triterpenes were present in Z. mobilis in significant amounts, comparable to those of diploptene, which is usually the major triterpenic hydrocarbon in hopanoid‐producing bacteria. The occurrence of such compounds confirms the lack of specificity of bacterial squalene cyclases and the possibility of alternative cyclization routes induced by the existence in the cyclization process of intermediate carbocations of sufficient lifetime.