1) Nucleobases quench the UV quanta by converting the energy into heat.
The heating, however, is not harmless. Using the approach of Dancshazy
and co-workers [210], it is possible to surmise that a single UV quantum
should locally heat a 100-unit RNA-like polymer by tens of degrees
Celsius. Even if the absorbed energy can be promptly transmitted to a
template, local heating of the template can eventually cause ablation of the
molecule [211]. In the UV-irradiated environment, both outcomes could
lead to polymer deterioration. Overheating, however, can be avoided by
channelling part of the energy into work. For example, those zymes that
could serve as antennas and use the UV energy, e.g., for connecting nucleotides
together (as hypothesized by Skulachev [111]) had better survival
chances. This selective advantage of “working” polymers over the “idle”
ones is general in nature: it is applicable not only to the first ribozymes,
but also to the first proteins, as discussed in the next section.
1) Nucleobases quench the UV quanta by converting the energy into heat.The heating, however, is not harmless. Using the approach of Dancshazyand co-workers [210], it is possible to surmise that a single UV quantumshould locally heat a 100-unit RNA-like polymer by tens of degreesCelsius. Even if the absorbed energy can be promptly transmitted to atemplate, local heating of the template can eventually cause ablation of themolecule [211]. In the UV-irradiated environment, both outcomes couldlead to polymer deterioration. Overheating, however, can be avoided bychannelling part of the energy into work. For example, those zymes thatcould serve as antennas and use the UV energy, e.g., for connecting nucleotidestogether (as hypothesized by Skulachev [111]) had better survivalchances. This selective advantage of “working” polymers over the “idle”ones is general in nature: it is applicable not only to the first ribozymes,but also to the first proteins, as discussed in the next section.
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