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GENE NUMBERS. "The number of genes ranges from about 1000 in bacteria to more than 400,000 in many flowering plants. Each species consists of many organisms and virtually no two members of the same species are genetically identical." This kind of data is commonplace. But how many genes are there in the entire world? A harder nut to crack. https://lnkd.in/egvZAuQ View in LinkedIn

FRAGMENT FROM NATURE features a singular paper from 2015 by Hanna K. E. Landenmark a graduate student, and Professor Charles S Cockell, from the University of Edinburgh's United Kingdom Centre for Astrobiology, entitled "An Estimate of the Total DNA in the Biosphere". The sheer calculation gymnastics deserves being singled out for merit. It s also a novel way to measure diversity. Enjoy! View in LinkedIn

LARGE RNA VIRUS POPULATIONS. "Possible examples of such hypersensitivity include overlapping reading frames, haploidy, and the loss of systems for genome repair." The hypersensitivity from the absence of redundancy mechanisms due to genome streamlining and a minimal genetic repertoire. https://lnkd.in/e9KGgbm View in LinkedIn

GENETIC STREAMLINING in large population microorganisms further complicates the need for high mutation rates as a consequence of the selective drive for rapid breeding cycles. http://www.nature.com/ismej/journal/v8/n8/full/ismej201460a.html View in LinkedIn

MASKING DELETERIOUS EFFECTS. "In small populations, such as those typical of most multicellular organisms, robustness evolves by masking the harmful effects of deleterious mutations, often by making certain functions redundant. Examples of such mechanisms include gene duplication, alternative metabolic pathways, or chaperone proteins that buffer against mutation-induced problems in other enzymes." https://lnkd.in/e9KGgbm View in LinkedIn

POPULATION SIZE FACTOR. "Mutational robustness (i.e., the ability to preserve a constant phenotype despite the genomic mutational load) can be achieved by two distinct mechanisms, each operating at a different range of population sizes." (In RNA viruses). https://lnkd.in/e9KGgbm View in LinkedIn

THE RACE FOR SPEED. "Did a high mutation rate emerge as a side effect of selection for faster replication? Biochemical assays of HIV-1 mutants resistant to nucleoside reverse transcriptase inhibitors suggest that this might be the case" in RNA viruses. https://lnkd.in/e9KGgbm View in LinkedIn

BIOSPHERE PROCESSING SPEEDS. "Given conservative estimates regarding DNA transcription rates, this information content suggests biosphere processing speeds exceeding yottaNOPS values 10(24)." (NOPS: Nucleotide Operations Per Second). https://lnkd.in/ewABXeK View in LinkedIn

NET EFFECT BALANCE. "Implicitly, the paradigm that high mutation rates allow for fast adaptation is based on the assumption that, with considerable frequency, the effect of beneficial mutations is strong enough to overcome the burden imposed by deleterious mutations, hence allowing for the hitchhiking of mutator strains with beneficial mutations." (RNA viruses). https://lnkd.in/e9KGgbm View in LinkedIn

TIME FROM DNA TO PROTEIN. "The average human gene is about 28,000 bases long, with only about 5% of it encoding for protein, which on an average is about 450 amino acids long. The major steps that take some time are: Transcription [DNA → pre-mRNA]: ~20min; Splicing [pre-mRNA → mature mRNA]: 5-10min; Transport [mRNA from nucleus to cytoplasm]: 10-30min; Translation [mRNA → Protein]: 90sec." https://lnkd.in/e2Z6svw View in LinkedIn