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Deacetylation

2018-10-23T17:37:43Z

170085463: Created page with "Deacetylation is the process which acetyl group is removed from chemical compound. == Gene Trancription Repression == Histone Deacetylases (HDAC) are chromatin modifying ..."

Deacetylation is the process which acetyl group is removed from chemical compound. 

== Gene Trancription Repression ==

Histone Deacetylases (HDAC) are chromatin modifying factor. HDAC can remove acetyl from histone to allow DNA to wrap more tightly to prevent trancription.<ref>Sumana C, Salil SP, Swati M, Nitin K, Karisetty BC, Arvind K. Chapter Four - Epigenetic Regulatory Mechanisms in Stress-Induced Behavior, fckLRInternational Review of Neurobiology. 2014:115:117-154.</ref>

 

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Rolling circle replication

2017-12-05T17:17:05Z

170085463: Created page with " Rolling circle replication is a process which a circular DNA or RNA molecule is replicated in one direction. This particular process occurs in plasmid and virus’s ge..."

Rolling circle replication is a process which a circular DNA or RNA molecule is replicated in one direction. This particular process occurs in plasmid and virus’s genome. 

=   Rolling Circle Replication Mechanism in DNA =

The process in DNA is initiated by initiator protein which nicks at the site called the double stranded origin on one strand of the double-strand. The initiator protein remains on the 5’ phosphate nick strand, and the 3’ hydroxyl end of the nick strand is elongated by DNA polymerase III. The unnicked strand acts as the template strand for replication and the 5’ phosphate nick strand is displace by helicase. Eventually, the nick strand is completely displaced by newly synthesis strand and will remove itself from the original circular DNA by the same initiator protein nicking at the terminating sequence on the nick strand. The nick strand then form a new single stranded circular DNA molecule. RNA polymerase and DNA polymerase III then use the single strand as template to form new double stranded circular DNA molecule<ref>Ruiz-Masó J, MachóN C, Bordanaba-Ruiseco L, Espinosa M, Coll M, Del Solar G. Plasmid rolling-circle replication. microbiolspectrum. 2015;3;10.1128</ref>. 

 

[[Image:RollingCircleReplication.jpg|center|700px|Mechanism of rolling circle replication in DNA]] 

 

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File:RollingCircleReplication.jpg

2017-12-05T17:07:47Z

170085463: Rolling Circle Replication

Rolling Circle Replication

Hypoxanthine

2017-12-05T11:44:47Z

170085463: Created page with " Hypoxanthine is a purine naturally found in human body and tends to be a component of nucleic acids<ref>Jarvis H, Marc O. Biochemical Methods of Estimating the Time Since D..."

Hypoxanthine is a purine naturally found in human body and tends to be a component of nucleic acids<ref>Jarvis H, Marc O. Biochemical Methods of Estimating the Time Since Death. Human Body Decomposition. 2016;3;53-90.</ref>. Hypoxanthine also can be founded as intermediates during adenine degradation. Specifically, when purine nucleoside phosphorylates reacts with inosine will create hypoxanthine. Afterward, hypoxanthine is converted into xanthine by xanthine oxidase<ref>Paul GW, Christopher JM, Vivienne RW, David RB, Mone Z. Free radical pathways in the inflammatory response. New Comprehensive Biochemistry. 1994;28;361-383.</ref>. Another way that hypoxanthine can formed is from deamination of adenine. This particular formation of hypoxanthine can result in mutation in transcription or DNA replication because hypoxanthine has similar structure to guanine; thus, hypoxanthine will be read as guanine and will form hydrogen bond with cytosine<ref>Berg JM, Tymoczko JL, Stryer L. Mutations Involve Changes in the Base Sequence of DNA. Biochemistry. 2002;527.6</ref>.

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