Abstract:
"Cyanobacteria and micro-algae are micro-organisms whose potential is largely untapped. It is well-known that upon storage and continuous utilization of micro-organisms in industries, changes in genetic materials occur. The aims of the experiments are to characterize local isolates of Synechococcus sp., Chlorella spp., and Scenedesmus spp. by RAPD-PCR fingerprinting and 16S rDNA sequencing and obtain intracellular protein profiles of mid-log phase, early stationary phase, and late stationary phase cells. Pure cultures of one strain of Synechococcus sp., six strains of Chlorella spp., and nine strains of Scenedesmus spp. were obtained and deposited at Microbiological Resources Center (Bangkok MIRCEN) under the following codes : TISTR 8867;TISTR 8852 to TISTR 8857;and TISTR 8858 to TISTR 8866. Intracellular protein profiles were obtained by SDS-PAGE. Results revealed the following primers (27f, 343r, 519r, 787r, 907r, 1100r, 1241f, 1385r, and 1492r) which were normally used to obtain Gram negative E. coli 16S rDNA sequence could be used to obtain RAPD-PCR fingerprints of all isolated cultures (primers 27f, 343r, 1100r, 1492r and CRL-7). 16S rDNA sequences of Synechococcus sp. TISTR 8867, and chloroplast 16S rDNA of Chlorella sp. TISTR 8852 and Scenedesmus sp.TISTR 8859 were also obtained with the use of all the nine primers. SDS-PAGE separation of proteins indicated cells of Synechococcus sp. TISTR 8867, Chlorella sp. TISTR 8852, and Scenedesmus sp. TISTR 8859 at different stages of growth exhibited similar intracellular protein profiles. Polypeptides 46, 16.5, 15 and 14 kDa were found in abundance in Chlorella sp. TISTR 8852 while more polypeptide 23 kDa was found in Synechococcus sp. TISTR 8867 and Scenedesmus sp. TISTR 8859. Polypeptide 43 kDa may be specific for prokaryotic cyanobacteria. Molecular data obtained in this research are not only useful for industrial applications but also contribute to the advancement of molecular genetics research on cyanobacteria and micro-algae in Thailand.