Month: September 2022

DNA IN BIOMASS. "The DNA is incorporated within approximately 2 × 10(12) tonnes of biomass and approximately 5 × 10(30) living cells, the latter dominated by prokaryotes." https://lnkd.in/ewABXeK View in LinkedIn

FUTURE PROSPECTS. "We might also wonder about the future computational power of the biosphere. In the next billion years or more, will the information content or the computational speed increase, and how will they be distributed amongst the major domains and subgroups of life?" https://lnkd.in/ewABXeK View in LinkedIn

SO ENDS this fragment from nature featuring a lively paper about the amount of global DNA as a way of looking at biodiversity. Quite charming. And one perspective is that life appears to have been driven in part to accumulate genetic information in the form of DNA, and this information is liberally shared among the planet's inhabitants. It's all about information. View in LinkedIn

RNA VS DNA VIRUSES. "A major challenge for understanding the evolution of mutation rates is the question of why DNA and RNA viruses, which apparently share similar lifestyles, show such different mutation rates...RNA viruses have elevated mutation rates because this confers increased adaptability, then why do DNA viruses maintain proofreading mechanisms?" https://lnkd.in/e9KGgbm View in LinkedIn

PROOFREADING IN DNA VIRUSES. " It is well known that DNA polymerases can be fully functional without 3′→5′ exonuclease activity, and hence, a DNA virus carrying a loss-of-function mutation should benefit from faster adaptation, eventually displacing strains with proofreading ability." https://lnkd.in/e9KGgbm View in LinkedIn

DNA VIRUS PROOFREADING KNOCKOUTS. "This apparent contradiction can be solved by noting that in RNA viruses, genetic information is even more compressed than it is in DNA viruses, because replication and transcription are biochemically equivalent, often catalyzed by a common molecular complex, and, in the case of positive-stranded RNA viruses, based on the same RNA molecule."" " https://lnkd.in/e9KGgbm View in LinkedIn

POSSIBLE EXPLANATIONS for the differences in mutation rate between RNA and DNA viruses include: Genetic hitchhiking, selection for fast replication, antiredundancy selection, and evolution of neutral networks. Excellent summary. https://lnkd.in/e9KGgbm View in LinkedIn

DNA EDITING is a critical part of replication for non-virus or non-bacterial swarm lifestyles. If the replicated genetic information contains errors from the process, these errors in the genetic code will often have serious or lethal consequences. And given the frequency and speed of DNA replication, highly efficient proof-reading is necessary. With increased molecular sophistication comes the need for another layer of complexity. The eukaryotic dilemma. View in LinkedIn

MOLECULAR SOPHISTICATION or baggage? View in LinkedIn

HIGH FIDELITY VS DIVERSITY. Two opposing pressures in nature are, on the one hand, the need for high fidelity replication of the DNA in multicellular animals with slow reproductive rates. On the other hand is the profound drive in rapidly reproducing viruses for instance, for enormous genetic diversity and mutation to rapidly adapt to new niches. View in LinkedIn