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A photosynthetic bacterium strain KUP-74 producing high amount of δ-aminolevulinic acid(ALA) was isolated from soils, which was identified as Rhodocyclus gelatinosus. After 10 days cultivation under anaerobic-light condition at 30℃, 4 Klux and pH 6.8, 5 ㎎/ℓ of ALA was formed extracellularly. ALA productions were increased up to 8 ㎎/ℓ and 12 ㎎/ℓ in cell cultivations either by the addition of 0.5% glycerol (v/v) or 10 mM of glycine and succinic acid, respectively, using Lascelles basil medium eliminated L-glutamic acid. By cultivation in the presence of 30 mM each D,L-glutamic acids and D,L-glutamines the yield of ALA showing a late induction phenomenon was reached the maximum value of 21 ㎎/ℓ. Different culture times were needed to generate maximum ALA yields by the addition of initial precursors of C₄ and C_5 pathways in basal medium, as being 107 h and 262 h, respectively. 40 ㎎/ℓ yield of ALA was observed by cell cultivation with the basal medium containing each 10 mM levulinic acid(LA) and glycine simultaneously.
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