Screening and identification of water microorganisms from Sungai Kelantan, Tanah Merah to determine the diversity of Microbiota

River is classified as freshwater ecosystem which contains various type of microorganism. Some of water microorganism can be an indicator for river water quality. The aim of this study is to investigate the diversity of microorganism in Sungai Tanah Merah. The water samples were taken and isolation of these microorganisms had been done by using serial dilution and streaking method. The morphology of pure colony of bacteria was done by using gram staining method in order to differentiate the bacteria according to their group, gram positive and gram negative bacteria and it also used as it serve the simplest test to observe the morphology of bacteria present in river water. As a result, five gram positive and three gram positive bacteria found in that study area. Pure colony of bacteria was cultured in Luria Broth. Cultured bacteria were used for DNA extraction in order to isolate DNA from bacteria sample. Polymerase Chain Reaction (PCR) was conducted for 30 cycles. The result showed multiple bands in PCR products which indicate that the samples were contaminated with organic substance such as salts. However, morphological of bacteria cannot be used to determine bacteria at species level. Therefore, further study on molecular based method must be conducted.