Friday, December 18, 2015

New class of DNA repair enzyme discovered

Over and over we are finding repair mechanisms that fight mutations and copying errors. Complex language that has meaning forward, backward and with layering.  Where is the evidence leading?

Life is super complex and has purpose. The information to direct it came from a mind.

New class of DNA repair enzyme discovered October 29, 2015

A new class of DNA repair enzyme has been discovered which demonstrates that a much broader range of damage can be removed from the double helix in ways that biologists did not think were possible.

According to the researchers, the AlkD mechanism has some remarkable properties:
  • It can recognize damaged bases indirectly. AlkD identifies lesions by interacting with the DNA backbone without contacting the damaged base itself.
  • It can repair many different types of lesions as long as they are positively charged. By contrast, the base-flipping mechanism used by other glycosylases relies on a relatively tight binding pocket in the enzyme, so each glycosylase is designed to work with a limited number of lesions. AlkD doesn't have the same type of pocket so it isn't restricted in the same way. Instead, the catalytic mechanism that AlkD uses is limited to removing positively charged lesions.
  • It can excise much bulkier lesions than other glycosylases. Base excision repair is generally limited to relatively small lesions. A different pathway, called nucleotide excision repair, handles larger lesions like those caused by UV radiation damage. However, Eichman's team discovered that AlkD could excise extremely bulky lesions, such as the one caused by the antibiotic yatakemycin, which is beyond the capability of other glycosylases.

Front Loading? Genetic Entropy? Complexity to simplicity?—The view that animals have become more complex over time could be a thing of the past, according to the latest research.

The new evidence, from scientists at the University of St Andrews, suggests that some modern day animals may have evolved instead by becoming less complex. 

Our Fragile Intellect

"Taken together, the large number of genes required for intellectual and emotional function, and the unique susceptibility of these genes to loss of heterozygosity, lead me to conclude that we, as a species, are surprisingly intellectually fragile and perhaps reached a peak 2000–6000 years ago. But if we are losing our intellectual abilities, how did we acquire them in the first place? This will be the topic of the next section [15]. "


You do the math......... 

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