Production of wax esters during aerobic growth of marine bacteria on isoprenoid compounds

This paper describes the production of isoprenoid wax esters during the aer obic degradation of 6,10,14-trimethylpentadecan-2-one and phytol by four ba cteria (Acinetobacter sp, strain PHY9, Pseudomonas nautica [IP85/617], Mari nobacter sp, strain CAB [DSMZ 11874], and Marinobacter hydrocarbonoclasticu s [ATCC 49840]) isolated from the marine environment. Different pathways ar e proposed to explain the formation of these compounds. In the case of 6,10 ,14-trimethylpentadecan-2-one, these esters result from the condensation of some acidic and alcoholic metabolites produced during the biodegradation, while phytol constitutes the alcohol moiety of most of the esters produced during growth on this isoprenoid alcohol. The amount of these esters formed increased considerably in N-limited cultures, in which the ammonium concen tration corresponds to conditions often found in marine sediments. This sug gests that the bacterial formation of isoprenoid wax esters might be favore d in such environments. Although conflicting evidence exists regarding the stability of these esters in sediments, it seems likely that, under some co nditions, bacterial esterification can enhance the preservation potential o f labile compounds such as phytol.