Page 110 - The Miraculous Machine that Works for an Entire Lifetime: Enzyme

Harun Yahya

METABOLIC PATHWAY OF DNA REPAIR
Types of damage

UV
Glycosylase Ligase
Oxidation that identifies
damage
Repaired
a DNA
Alkylation

Deamination

DNA is a giant molecule containing a data bank of 3 billion "letters." Every
stage during the replication of this molecule is supervised by enzymes. If any
error arises during the process, it is immediately corrected and the chain is
checked again. It is scientifically obvious that such a conscious system could
not come into being by chance.

DNA is a giant molecule consisting of a data bank of 3 billion "let-
ters." This molecule resembles a spiral staircase twisted into a helix
shape. When replication first begins, the enzyme known as DNA heli-
case separates the two DNA strands like a zipper, at a rate of up to 1,000

nucleotide pairs a second.
As it opens the zipper, DNA helicase suddenly stops at the points
that represent the limits of the information required. (When a process is
to be carried out in the cell, only that part of the DNA code concerning
that process is copied.) The enzymes know how far the information ex-
tends and how far the DNA helix needs to be pried apart.
In principle, the unwinding of the DNA helix is made possible by

two DNA helicase enzymes acting together. One runs along the leading
strand template, while the other runs along the lagging strand tem-
plate. Since the two strands have opposite polarities, these helicases
must move in opposite directions on the DNA strand, for which reason

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