CHARACTERIZATION OF PHOTOSYNTHETIC GLYCOGEN AND ALPHA-GLUCOSIDASE FROM THERMOPHILIC CYANOBACTERIA, LYNGBYA-PHORMIDIUM-PLECTONEMA GROUP-B

We harvested filamentous cyanobacteria from an alkaline hot spring (45 -50 degrees C, pH 8.5-9.0) in Kagoshima Prefecture, and identified it as Lyngbya-Phormidium-Plectonema (LPP) group B by morphological charac teristics. From the TCA-soluble fraction of the LPP group B, we isolat ed glycogen with average chain length of 11 glucose units. The glycoge n showed a similar iodine absorption spectrum to that of rabbit liver glycogen. We also recognized the presence of the TCA-insoluble glycoge n at about 48% of total glycogen, most of which was bound non-covalent ly to protein and showed similar iodine absorption spectrum to that of the TCA-soluble glycogen. We also found thermophilic and thermostable alpha-glucosidase with optimum pH 6.5 in this cyanobacteria.