Celina Pinto/Sandbox 211: Difference between revisions
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T5 5'-exonuclease is a homodimeric protein composed of two identical chains, <scene name='Celina_Pinto/Sandbox_211/Chain_a/2'>chain a</scene> and chain b. Both chains contain a hole, bound by a helical arch composed of two helices in which hydrophobic and positively charged residues are located. The helical arch is situated in front of the active site and only single-stranded DNA can pass through it. Since the enzyme is able to cleave double-stranded DNA, the enzyme has a conformational flexibility to facilitate DNA threading which is required to process the 5' nuclease substrates in the active site. | T5 5'-exonuclease is a homodimeric protein composed of two identical chains, <scene name='Celina_Pinto/Sandbox_211/Chain_a/2'>chain a</scene> and <scene name='Celina_Pinto/Sandbox_211/Chain_b/1'>chain b</scene>. Both chains contain a hole, bound by a helical arch composed of two helices in which hydrophobic and positively charged residues are located. The helical arch is situated in front of the active site and only single-stranded DNA can pass through it. Since the enzyme is able to cleave double-stranded DNA, the enzyme has a conformational flexibility to facilitate DNA threading which is required to process the 5' nuclease substrates in the active site. | ||
The core regions of the enzyme are composed of beta-sheets and alpha-helices . These form the base of the active site pocket which bind the catalytic metal ions. | The core regions of the enzyme are composed of beta-sheets and alpha-helices . These form the base of the active site pocket which bind the catalytic metal ions. | ||