Ez nem csak úgy magától pöndörödik, ezt pöndöríteni kell ! ... Ez komplett gyártási folyamat:
In every cell, DNA supercoiling is a precisely regulated process that influences many
aspects of DNA metabolism. Not surprisingly, there are enzymes in every cell whose sole
purpose is to underwind and/or relax DNA. The enzymes that increase or decrease the extent
of DNA underwinding are called topoisomerases, and the property of DNA
they affect is the linking number. These enzymes play an especially important role in
processes such as replication and DNA packaging. There are two classes of topoisomerases.
Type 1 topoisomerases act by transiently breaking one of the two DNA strands, rotating one
of the ends about the unbroken strand, and rejoining the broken ends; they change Lk
in increments of 1. Type 2 topoisomerases break both DNA strands and change Lk in
increments of 2.
Lehninger-Nelson-Cox: Principles of Biochemistry, 805.o.
homeostasis : The maintenance of a dynamic steady state by regulatory mechanisms that compensate for changes in external circumstances. ___...
We begin in each case by considering the covalent structure of the simple subunits (amino acids, fatty acids, monosaccharides, and nucleoti...
"Some proteins endow cells and organisms with the ability to contract, to change shape, or to move about. Actin and myosin function...
Ez nem csak úgy magától pöndörödik, ezt pöndöríteni kell ! ... Ez komplett gyártási folyamat: In every cell, DNA supercoiling is a preci...