Recombination from a Biochemical Perspective


Over 25 different different enzymes are involved in homologous recombination in enteric bacteria. The following list includes some of the important players.

These enzymes function together to result in recombination via the molecular mechanism shown on the link Recombination from a Molecular Perspective. .

Some important points to remember about the biochemistry of homologous recombination are:

  1. Homologous recombination requires RecA protein.
  2. Homologous recombination requires substantial DNA sequence homology between the donor and recipient DNA.
  3. Recombination results from the cutting of two DNA strands between phosphodiester bonds, and the covalent rejoining of the DNA strands.
  4. Recombination is a complex process involving many different enzymes, and many redundant functions.
These biochemical points explain some very important practical aspects of genetic recombination:
  1. Recombination between any two sequences is a relatively low frequency event.
  2. Because the cutting-rejoining of phosphodiester bonds can occur between any adjacent nucleotides within a homologous pair of DNA molecules, the co-inheritance of two genetic markers is inversely proportional to the distance between the markers.

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Last modified September 25, 2004