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When cells of Escherichia coli were suspended in dilute artificial seawater and cooled to various subzero temperatures, a maximum lethal effect occurred around −40 °C. In addition, rapid cooling to −26 °C of bacteria, suspended in concentrated, non-freezing seawater caused a pronounced decrease in viability ("cold shock"). The loss in viability was accompanied by a proportional release from the cells of ultraviolet-absorbing material and by an increase in the ribose and organic phosphorus contents of the suspending liquid. It seems possible that the released material, at least partly, consisted of nucleotides or nucleic acids.

Addilion of oclanoic acid (2 • 10"^ M) to the suspending medium (final pH 4.85) of Bolettt.i uariegattts mycelium induced a marked leaking of UV absorhing substances from the celts. Ttie materiat hiid an absorption maximum at 260 nm, a minimum at 240 11111, and the absorption ratios 250: 260 and 280: 260 were 0.81 and 0.49.The material released immediately after addition of the acid consisted mainly of tow molecular weight substances. These suhslances, listed according to decreasing rates of leaking, were identified as pentoses, pentose])liosphates, nucteosides, and mono-and di-uucleotides. Also, puriiie and pyriniidine bases were released at this early stage of treatment.After 90 minutes' treatment, an outflux of oligoribonucleotides was observed. Ttie oligorihonucleoUdes did not occur as single subslances, hut were forming complexes with peptides. Minor amouuls of riboniicleic acid were also leaking out from the cetls. Deoxyribose containing substances were never observed in Ihc filtrates.The compounds were subjected to euzyniatic degradation after tbey had left tlie cells. Ttiis was shown by a marked increase with time of inorganic phosphorus, pentose/pentoseiibosphates, and nucleosides in the fittrate.Ttie teaking of low molecutar weight suhstances immediately after acid addition is correlated to seriously reduced growth. However, the growth was wliolly restored after a tliree days' lag period. Ou the other hand, when considerable amounts of otigorihonucleotide peptides had been released from the cells, growth could not be re-estabtistied. i

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