Uncoordination and recoordination in Spirillum volutans

Abstract

The quantitative effects of several new uncoordinating agents for Spirillum volutans were studied. A new type of uncoordination, "dual-straight-tail," was described for polyethylene glycol or HgCl2. Certain agents caused a mixture of more than one type of uncoordination. Exposure of normal cells to pH 4.4 caused dual-tail uncoordination, while pH 9.9 caused dual-head. Recoordination of cells was accomplished by washing cells free of agent, application of metal-complexing agents, or, in the case of uncoordination by pH, readjustment of pH. Protein synthesis was not required for recoordination. All agents tested caused substantial decreases in oxygen consumption at their uncoordinating concentrations, but this was not the cause of uncoordination since normal coordinated states could be maintained with every cell for prolonged periods in the absence of detectable respiration, even in the presence of cyanide. Stroboscopic measurements indicated decreased flagellar rotational speeds in uncoordinated cells. In an electric field, the act of reversing polarity or of breaking or closing the circuit caused motile coordinated cells to instantly reverse whatever direction in which they had been previously swimming. Electric fields did not cause alignment of the motile spirilla.