Synthesis of anabiosis autoinducers by non-spore-forming bacteria as a mechanism regulating their activity in soil and subsoil sedimentary rocks

Non-spore-forming bacteria of the genera Arthrobacter and Micrococcus, isol ated from permafrost subsoil, were found to produce greater amounts of the d(1) extracellular factor than closely related collection strains isolated from soil. The effect of this factor, responsible for cell transition to an abiosis, was not species-specific. Thus, the d(1) preparation isolated from the culture liquid of the permafrost isolate Arthrobacter globiformis 245 produced an effect on the collection strain Arthrobacter globiformis B-1112 and also on Micrococcus luteus and Bacillus cereus. The d(1) preparation f rom the permafrost isolate of Arthrobacter differed from the chemical analo gue of this factor, 4-n-hexylresorcinol, in the level of the induced cell r esponse, which may have resulted from different cell sensitivity to various homologs of alkylhydroxybenzenes contained in the d(1) preparation. Thus, additional evidence was obtained indicating that autoregulation of bacteria l growth and development is implemented at the level of intercellular inter actions in microbial communities. Abundant production of the d(1) an anabio sis-inducing factors by bacteria isolated from permafrost subsoil is probab ly a result of special antistress mechanisms responsible for the survival o f these bacteria under extreme conditions of natural longterm cooling.