Increasing 5-Aminolevulinic acid Yield from Acidophilic/Acdotolerant Photosynthetic Bacteria by Radiation

Photosynthetic bacteria 120 isolates exhibited growth in medium pH 5.0, 5.5, 6.0 and 6.5 were measured for extracellular ALA production. The 9 isolates secreted 5-aminolevulinic acid in range of 2.41-4.84, 3.63-6.84 and 3.54-5.6 μM within 24,48 and 72 hours, respectively. Among the 9 isolates tested, CH17 gave the highest yield followed by PC18, PC15, PD13, PC16, PC14, KG5, PC13 and PD7, respectively. Extra cellular 5-aminolevulinic acid accumulation by the CH17 grown in the medium pH 5.5 was 4.86 and 6.84μM within 24 and 48 hours, respectively. Sine KG5 utilized different kinds of carbon source, thus isolated KG5 was selected for mutation. The results revealed that one mutation, KG5-1M secreted 5 aminolevulinic acid higher than of wild type, KG5 did.