Mechanistic studies on the phytylation step in bacteriochlorophyll a biosynthesis: an application of the 18O induced isotope effect in 13C n.m.r. spectroscopy
Abstract
It is show that bacteriochlorophyll a(3a) biosynthesised from [1-13C; 1,1,4-18O3]-5-aminolaevulinic acid (1, C*=13C; OΔ=18O) in growing cultures of Rhodopseudomonas sphaeroides contains oxygen-18 in both the bridge (16O13C–18O–) and non-bridge (18O
13C
16O–) oxygen of the phytyl ester linkage [–C(:O)–O–phytyl].