Isolation and characterization of uncultured bacteria from wheat seeds, soil and sponge

Author: Sharandeep Kaur

Kaur, Sharandeep, 2019 Isolation and characterization of uncultured bacteria from wheat seeds, soil and sponge, Flinders University, College of Medicine and Public Health

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Microorganisms are one of the oldest living forms present on the planet and yet microbiologists struggle to culture 90% of genera and study them in in vitro conditions. Samples of sponge, wheat seeds and soil for which more than half of their bacterial population cannot be cultured due to various reasons were selected for this study. In this study efforts were made to culture the as yet unculturable bacteria using different techniques. To achieve the growth of the uncultured bacteria in in vitro conditions, the dilutions to extinction was done (10-12 & 10-14) with the intention of achieving one cell per well and the samples were incubated in the 96-well plates at two different temperature conditions. The samples were subjected to long incubation (10-12 weeks). Other parameters were also tested like liquid v/s agar growth and the ones growing on agar were categorised and selected as per the nature of the growth. The ones which were not growing on agar were hypothesised to be more likely to be novel and therefore selected for sequencing of their 16S rRNA genes to identify the isolates. The bacterial strains growing on agar were categorised and some strains were not showing growth on the solid medium and hence they were suspected to be new bacteria. But after the sequencing of 26 isolates it was observed that the majority of strains belong to already commonly described species.

Keywords: Uncultured, Soil, Sponge, Wheat seeds

Subject: Biotechnology thesis

Thesis type: Masters
Completed: 2019
School: College of Medicine and Public Health
Supervisor: Chris Franco