Strand Binding Protein
Single strand binding protein can simply be defined as protein that binds to single-stranded DNA. This Process usually takes place near the replication fork for stabilization of the single strands. The SSB protein fights towards protecting the single stranded DNA from being consumed by the nucleases through the process of digestion. Besides, it also eliminates the secondary structure from the DNA so that other enzymes are able to effectively operate upon it.
Single stranded DNA can always be produced in every aspect of DNA metabolism. Such aspects include replication, repair and recombination. Single strand binding proteins are joined to numerous proteins that are involved in all processes of DNA metabolism. Besides, they are also very active in the modulation of these proteins. It should be noted that single strand binding proteins do not bind quite well to double stranded DNA.
DNA is usually stable when it is within a double helix under physiological conditions. However, this can only remain so if the complementary strands of DNA are in a similar location. After the double helix is separated by the enzyme helicase into single strands of DNA, there are higher chances that they try to re-construct the double helix. However, they need to be prevented from pursuing that course. The work of single strand binding protein is to ensure that these post-replication fork single strands of DNA do not regroup.
Single strand binding proteins are present in humans as well as bacteria and viruses. The only organisms that have not been found to contain the SSB proteins are Thermoproteales. The most ideal characterized single strand binding protein is obtained from bacteria known as E.coli. In this case, the SSB protein occupies a large number of DNA bases with regards to various factors. One of the main factors that play a role in this procedure is salt concentration.
DNA that has been changed from a double stranded form to a single stranded form can be said to have undergone denaturing. The objective of single strand binding protein is to prevent the denatured DNA from renaturing. It positions itself between two DNA strands that are undergoing replication or an individual one that is undergoing a similar process. However, emphasis is mainly placed on the latter.
A single strand binding protein ensures that even if it takes a long duration of time, renaturing of DNA does not take place. With this, there is no chance that replication of DNA shall take place. After this process, the work of the single strand binding protein is done and it is not needed anymore.
When studying single strand binding protein, it is important to also note that it binds to single stranded DNA in two different ways, limited and unlimited. Under limited, the protein clusters are only tied to the formation of dimmers of tetramers due to the interaction of four single strand binding subunits with single strand DNA. Under unlimited, there are chances of formation of long clusters of protein since they interact with one another on either sides of the protein that they are bound to.
At Essays Experts, we offer professional custom writing services that you can always acquire at your own convenience. We always guarantee original and top notch papers for all disciplines and levels.