Verus

Bacteria prevent infections by bacteriophages by using   The CRISPR/cas9 system cut viral genetic material. At the same time the bacteriophage develops techniques to bypass bacterial immune defense. The techniques  have been uncovered by researchers ; Anti-Crisper proteins. They  work by inhibiting CRISPR  complex from cleaving viral genome.  What is the significance of this? The ANTI-CRISPR proteins can be used to fine tune genetic modification in genetic engineering. The CRISPR/Cas system is specific and efficient  in genetic engineering  but not perfect. The imperfection is the result of off-targets mutations that is a flaw in the system. Off-target mutations can theoretically be prevented by using ATI-CRISPR system to control when CRISPR/Cas system mechanism is used to cleave a specific locus in the genome.   The question is; how does the ANTI-CRISPR proteins and CRISPR/cas system interact?

By: Faith I. 

Original Article: https://www.sciencedaily.com/releases/2016/12/161208143535.htm

Under harsh environmental conditions such as extreme fluctuations in temperature expression of genes are induced  that result in synthesis of proteins that enable the bacillus to survive. Also, bacillus can acquire exogenous compounds through transport system to survive fluctuations in temperature in order to prevent plasmolysis.

For example: When environment is very hot the bacillus is under osmotic stress because it’s in a hypertonic state.  The amount of dissolved solutes in bacillus cell is less than that in the environment. In other words the concentration of water is greater within bacillus cell than its environment; as result water moves from within the cell into the environment.  To survive bacillus accumulates compounds from environment to balance the difference in solute concentration. These compounds are known as osmoprotectants and can also be synthesized by the bacillus.  In addition, bacillus genome encode for osmoprotectants that are temperature sensitive such as chaperones and protease.