Studies in carotenogenesis. 10. Spirilloxanthin synthesis by washed cells of Rhodospirillum rubrum

Abstract

Studies in Carotenogenesis 10. SPIRILLOXANTHIN SYNTHESIS BY WASHED CELLS OF RHODOSPIRILLUM RUBRUM

The Isolation and Description of two Marine Micro-organisms with Special Reference to their Pigment Production

“…The action of diphenylamine on Euglena gracilis v. bacillaris (Goodwin & Jamikorn, unpublished observations) and Rhodopseudomonas spheroides (Goodwin, Land & Osman, unpublished observations), is similar to that on the coryneform pigments, but in Mycobacterium phlei (Turian, 1950 ;Turian & Haxo, 1952 ; Goodwin & Jamikorn, unpublished observations), Phycomyces blalcesleeanus (Goodwin, 1952 b;Goodwin, Jamikorn & Willmer, 1952) and Rhodospirillum rubrum (Goodwin & Osman, 1954), the synthesis of the carotenoids is inhibited whilst that of the colourless polyenes is stimulated.…”

“…This pigment is one of two (a-and P-bacteriopurpurin) obtained by Molisch ( 1907) from Bacterium rubescens. a-Bacteriopurpurin also occurs in Flavobacterium arborescerts (Sobin & Stahly, 1942), in Bacterium halobium (Lederer, 1938) and possibly in traces in Rhodospirillum rubrum (Goodwin & Osman, 1954) ; it is possibly demethylated rhodoviolascin (spirilloxanthin) (Karrer & Solmssen, 1935;Polghr, van Niel & Zechmeister, 1944). Although the experimental information is not complete, it is almost certain that all the purple sulphur and non-sulphur bacteria contain carotenoids along with bacteriochlorophyll (see Goodwin, 1952 a, for full details).…”

Adenosyl-methionine incorporation into the methoxylated carotenoids in chromatophores of Rhodospirillum rubrum.

“…For chromatophore preparations, 1 liter of log-phase culture was harvested by centrifugation and suspende'l in 0.1 At potassium phosphate pH 7 The reaction mixtures contained in molese: 100, potassium phosphate pH 7.5; 5, GSH; 10, MgCl2; with 1.0 ml of chromatophore suspension and either 10 /Amoles ATP with 10 Ac DL-methionine-methyl-C14 or 1.0 juc of S-adenosyl-methionine-methyl-Cl4. The reaction mix- Low concentrations of p-chloromercuribenzoate (p-CMB) inhibit C14-spirilloxanthin formation from S-adenosyl-methionine-methyl-Cl4 (table III) The total amount of S-a(lenosyl-nmetlhioniine-imiethyl-C14 incorporated into spirilloxanthin varies with the physiological age of the chroniatophores (table IV).…”

“…These reactions have been established by A) the identification and proof of structure of the individual carotenoids (2, 10, 12); B) analysis of changes in the individual carotenoi(Is (luring synthesis of spirilloxanthin in resting cells (6,7,9,13); and C) analysis of the labelling pattern of the lycopene (lerivatives from radioactive precursors (3, 4). Little is known regar(ling the nature of these reactions in isolate l articles.…”

The dehydrogenation sequence leading to coloured carotenoids in photosynthetic bacteria

“…A conjugated heptaene, assumed to be g-carotene, was isolated from diphenylamine-inhibited cultures of Rhodo8pirillum rubrum by Goodwin & Osman (1954). Jensen, Cohen-Bazire, Nakayama & Stanier (1958) showed that this compound, together with other precursors, disappeared when the inhibition was removed and they deduced that the Porter & Lincoln sequence operates in photosynthetic bacteria.…”