about results…

We have been working on identifying clones, from a genomic library of the Microbial Observatory in Cabo Rojo, that are capable of using complex sugars as their sole carbon source. We have isolated DNA from an environmental sample of the Microbial Observatory, cloned a DNA segment of 30 kb into a vector (plasmid), and transformed the clones into a host bacterium, Escherichia coli. My work has been to screen the resulting transformants in order to find clones which posess the enzymes necessary to degrade EPS.

Microbial degradation of EPS was assesses using Biolog to measure the optical density of the medium in which the clones where being culture. Optical density refers to the measure of the amount of light absorbed by a suspension of bacterial cells or a solution of an organic molecule. We are using these values to measure turbidity, which in turn helps us estimate the concentration of polysaccharide molecules in our medium.

As a culture medium we use M9 minimal salts, 5x. This medium is commonly used for the propagation of E. coli and for plasmid amplification.

To assess the degradation of EPS we used Biolog. Optical density values where used to measure turbidity and estimate the concentration of polysaccharide molecules in the medium. O.D. was measured at two different wavelengths, 750 nm and 590 nm.

We were able to measure the optical density in 376 clones. Optical density, in the medium, decreased after a considerable period of incubation. This is due to the decrease in the concentration of polysaccharide molecules.

We have now prepared our medium with a lower concentration of sugars. We think this will help us assess the degradation of EPS in a shorter period of time. Our ultimate research goal is to discover new genes and enzymes, with Biotechnological and Biomedical applications.

~ by Angel on November 26, 2008.