Laboratory Simulation of “Proteolytic Bacterium–Cyanobacterium” Interaction in Alkaliphilic Microbial Community

The work continues the series of long-term studies of the microbial diversity of soda lakes and concerns the problem of anaerobic decomposition of proteins. The physiology of new proteolytic bacteria has been investigated. The lytic effect of the alkaliphilic anaerobe Proteinivorax tanatarense on other members of community, primarily cyanobacteria, has been demonstrated. P. tanatarense proved to be a saprotrophic satellite regulating the number of cyanobacteria under night conditions. The directed effects of P. tanatarense on phototrophic and chemotrophic Gram-negative microorganisms were demonstrated as well as the absence of its effect on any Gram-positive microorganisms. Such specialization of proteolytic agent could be implemented in cyanobacterial communities of the past.