Isolation of Phaffia rhodozyma Mutants with Increased Astaxanthin Content

• DOI: 10.1128/aem.55.1.116-124.1989
• Publication Date: 2020-01-01T04:11:52Z
• Authors: Gil-Hwan An; Donald B. Schuman; Eric A. Johnson
• Keywords: Antimycin A; Yeast extract

Plating of the astaxanthin-producing yeast Phaffia rhodozyma onto yeast-malt agar containing 50 μM antimycin A gave rise to colonies unusual morphology, characterized by a nonpigmented lower smooth surface that developed highly pigmented vertical papillae after 1 2 months. Isolation and purification papillae, followed testing for pigment production in shake flasks, demonstrated several isolates were increased two- fivefold astaxanthin content compared with parental natural isolate (UCD-FST 67-385). One strains (ant-1) nitrosoguanidine derivative ant-1 (ant-1-4) produced considerably more than parent (ant-1 had 800 900 μg/g; ant-1-4 1,300 67-385 300 450 μg/g). The mutant physiologically parent. mutants grew slower on ammonia, glutamate, or glutamine as nitrogen sources also cell yields carbon sources. Although isolated plates, they found be susceptible A, apparently owing spatial separation from agar. They respiratory inhibitor thenoyltrifluoroacetone slightly cyanide, but did not differ susceptibility azide. antimycin-derived killed faster hydrogen peroxide. carotenoid compositions similar those previously determined type strain 67-210) except two carotenoids present quantities phoenicoxanthin was minor component. chemical properties unknown suggested tended oxygenate desaturate carotene precursors greater extent physiology known specificity cytochrome b chain suggests alteration P-450 components involved oxygenation desaturation carotenes mitochondria are affected, which results production. These astaxanthin-overproducing could useful providing source pen-reared-salmon industry other farmed animals contain their principal carotenoid.