MOLECULAR DETERMINATION OF A GREEN ALGAE ISOLATE TO DETECTING 1-Deoxy-D-Xylulose-5-phosphate Synthase (DXS) GENE IN IMPROVEMENT OF CAROTENOID PRODUCTION

Abstract

Carotenoids production levels are not yet competitive with carotenoid levels presently produced by fermentation, synthesis and isolation. It needs application of metabolic engineering and genetic engineering techniques in improving their production. An attempt to optimize carotenoid production from local isolate of green algae from BBAP Jepara has faced several problems, primarily related to the microbiological and eco-physiological characteristic which affecting growth that have not sufficiently been understood. A misnamed of species also have arisen due to wrong characterization. One local isolate of an algal species from BBAP Jepara was found potentially useful as source of carotenoids in food additives or as food supplement in fish farming. It was suspected as representing a strain of Dunaliella. Previous studies to improve carotenoid production using molecular approach on have shown unagreement. Therefore, the present study aimed to determinate the species of green algae isolate from Jepara waters based on molecular techniques using 23S rRNA approach for detecting DXS gene. Molecular analysis by 23S rRNA alignment showed the close relationship among isolate of green algae and most all of member of Cyanobacteria. Closest similarities was showed by Cyanobacterium sp. MBIC 1021 with 99 % similarity and Synechocystis PCC6308 with 95 % similarity. Synechocystis was the only member of Cyanobacteria which have DXS gene. Multiples aligment sequences of partial DXS gene on the conserve region among seven species confirmed this result. The DXS gene analysis also showed closest relationship between partial DXS gene of Cyanobacteria Synechocystis and a green algae isolate. The result of this analysis proven as valuable parameter for the interpretation of the relation among DXS gene of a green algae isolate and Cyanobacteria and increase the possibility in getting the complete DXS gene from local isolate of green algae by designing primers from DXS gene of Synechocystis as a member of Cyanobacteria.