Summary: | There are relatively few studies on the bacterial communities of the Antarctic snow.
Hence, this study was set out to analyze the bacterial communities from snow and to
determine whether there is any antagonistic interaction between them. Bacterial strains
were isolated from Antarctic snow and were differentiated. Forty six pure cultures were
isolated and inhibitory interactions between the bacteria were tested. Initially, non redundant
bacterial strains were selected through observation of the colony morphology,
bacterial phenotypic characteristics and molecular approach. Of the 46 bacterial isolates,
43 strains were Gram-negative and 3 strains were Gram-positive. Three different shapes
were obtained under the microscope. They were single bacilli, diplobacilli and cocci
shapes. Molecular characterization was carried out using random amplified polymorphic
DNA (RAPD). The RAPD data was analyzed by GelCompar II to construct phylogenetic
tree. The phylogenetic relations between the 46 isolates were defined based on cluster
of UPGMA. After the RAPD analysis, 10 distinct isolates were chosen for subsequent
antagonistic test. All the strains were tested for antagonistic interaction on the R2A solid
agar medium. Every single strain was used as 'target strain' once and the other strains
were used as the 'tester strain'. All the strains tested did not show inhibitory effects
toward each other. This indicates there are no antagonistic interactions between the
selected strains. However, one bacteria strain was found exhibit interesting grow feature
by performing autolysis when it was cultured on all bacteria strains. Studies would be
needed to know more about the bacteria strain and to confirm the hypothesis made.
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