Hydroxy-3,4-dehydro-apo-8′-lycopene and methyl hydroxy-3,4-dehydro-apo-8′-lycopenoate, novel C30 carotenoids produced by a mutant of marine bacterium Halobacillus halophilus

Abstract

We performed the chemical mutagenesis of Halobacillus halophilus (the producer of a C 30 carotenoid, methyl glucosyl-3,4-dehydro-apo-8¢-lycopenoate) to isolate novel carotenoids that are biosynthetic intermediates of methyl glucosyl-3,4-dehydroapo-8¢-lycopenoate. As a result, we isolated two novel C 30 carotenoids, hydroxy-3,4-dehydro-apo-8¢-lycopene and methyl hydroxy-3,4-dehydro-apo-8¢-lycopenoate, which were biosynthesized through a novel 8¢-apo C 30 pathway. These carotenoids showed antioxidative activity in the 1 O 2 suppression model.

Identification and the developmental formation of carotenoid pigments in the yellow/orange Bacillus spore-formers

“…C 40 and C 30 4,4′-diapocarotenoids are symmetric terpenoids in which a system of three conjugated double bounds is located in the centre of the molecule, as a result of the combination of two identical precursors. However, NMR analysis [11,17,18] revealed that C 30 apo-8′-carotenoids are not symmetric as the 3 conjugated double bounds are not located in the core of the structure. This leads to the hypothesis that the original prenylated precursors might be C 20 and C 10 precursors instead of two C 15 molecules (Fig.…”

“…The latter are generally referred to as 4,4′-diapocarotenoids and are typically found in a limited number of Gram +ve bacteria such as Methylobacterium rhodinum (formally Pseudomonas rhodos) [12,24,25], Streptococcus faecium [26], Heliobacteria [20,27], and Staphylococcus aureus [15,28,29]. However, triterpenoids recently identified in the Gram +ve bacteria Planococcus [18] and Halobacillus have been described as 8′-apocarotenoids [17] instead of 4,4′-diapocarotenoids. C 40 and C 30 4,4′-diapocarotenoids are symmetric terpenoids in which a system of three conjugated double bounds is located in the centre of the molecule, as a result of the combination of two identical precursors.…”

“…Not all organisms are capable of synthesising carotenoids de novo, instead their formation is restricted to the secondary metabolism of plants, algae and certain groups of fungi and bacteria [8,9]. In higher plants, algae and fungi the carotenoids produced contain a C 40 scaffold [9,10], whilst bacteria can produce a diverse range of carotenoids with both C 40 and C 30 backbones [11][12][13][14][15][16][17][18][19][20][21][22]. The origin of this structural diversity resides from the prenyl diphosphates precursors utilised in the first committed step of carotenoid biosynthesis [23].…”

Annotation and functional assignment of the genes for the C30 carotenoid pathways from the genomes of two bacteria: Bacillus indicus and Bacillus firmus

“…et al Kim & Lee, 2012), and the modification of CrtNb from a diketolase to a monoketolase determines the diversion to 4-glycosyl-49-methyl-4,49-diapolycopen-49-oate fatty acid esters (Shindo et al, 2008;Osawa et al, 2010).…”

“…In addition, C 30 carotenoids are group specific, as in the case of heliobacteria (Takaichi et al, 2003) and pigmented Bacillales. Bacteria from the latter group with a well-established C 30 carotenoid pathway include Planococcus maritimus (Shindo et al, 2008), Halobacillus halophilus (Osawa et al, 2010) and Sporosarcina aquimarina (Steiger et al, 2012a).…”