Chemotaxis, sporulation, and larvicide production in Bacillus sphaericus 2362

Abstract

CAminophenylboronic acid (APBA), a known inhibitor of sporulation in Bacilli, as well as L-ethionine, a known inhibitor of chemotaxis in Enterobacteria, inhibited both sporulation and chemotactic behavior but not growth of BaciZZus sphaericus. Both compounds also inhibited the methyl group turnover on the methyl-accepting chemotaxis protein (P53) in this microorganism. Sporulation of B. spbaericus was inhibited only when APBA was added to the growing culture before the late logarithmic stage. It was previously demonstrated that the ability of B. sphuericus to respond to chemoattractants sharply declines at the same age of the culture. Thus, it seems plausible that the action of both inhibitors upon sporulation may be attributed to the inhibition of some regulatory pathway common to chemotaxis and sporulation and involving protein methylation. Possible exchange of the nutrient depletion-related sensory information between chemotaxis and sporulation systems at the level of methyl group transfer is discussed.

Evidence of a role for NAD+-glycohydrolase and ADP-ribosyltransferase in growth and differentiation of Streptomyces griseus NRRL B-2682: inhibition by m-aminophenylboronic acid

“…To have this effect, APBA must be added before the onset of late exponential growth. APBA may inhibit a regulatory pathway common t o sporulation and chemotaxis and as a result inhibit methyl group turnover in the methylaccepting protein of B. sphaericus (Andrew et al, 1994). However, the molecular target of APBA is not known.…”

Altered chemotaxis of a Bacillus sphaericusl‐ethionine‐resistant sporulation mutant a probable link between chemotaxis and sporulation

“…This paradox indicated, in our opinion, an additional regulatory function for MCP transmethylation, besides mediation of chemotactic signals. Indeed, the transition from the mid-to late-logarithmic stage of growth coincided not only with the loss of sensory com- ponent of chemotactic response but also with the commitment of B. sphaericus cells to undergo sporulation [4]. 4-Aminophenylboronic acid (APBA), a known inhibitor of sporulation in Bacilli, as well as L-ethionine, a known inhibitor of bacterial chemotaxis inhibited sporulation, chemotaxis and methyl group turnover on the MCP of B. sphaericus [4].…”

“…Indeed, the transition from the mid-to late-logarithmic stage of growth coincided not only with the loss of sensory com- ponent of chemotactic response but also with the commitment of B. sphaericus cells to undergo sporulation [4]. 4-Aminophenylboronic acid (APBA), a known inhibitor of sporulation in Bacilli, as well as L-ethionine, a known inhibitor of bacterial chemotaxis inhibited sporulation, chemotaxis and methyl group turnover on the MCP of B. sphaericus [4]. The mutual effect of inhibitors upon chemotaxis and sporulation was attributed to a common regulatory pathway involving protein transmethylation.…”

“…The culture was then heated at 80°C for 10 min. The particulate material was harvested, transferred into glutamate-based medium [4] containing L-ethionine (10 mM), grown for 24 h and heated at 80°C for 10 min. After repeating the selection cycle, this time with inoculation rates of 0.5% between the transfers, the spores were plated on Nutrient agar (DIFCO).…”