Salt stress induction of glutamyl endopeptidase biosynthesis in Bacillus intermedius

Abstract

Bacteria from the genus Bacillus have evolved complicated regulatory networks to be protected from various environmental stresses, including sudden increase in salinity. Among these regulatory mechanisms is the DegS-DegU signal transduction system, which controls degradative enzyme synthesis and is involved in sensing salt stress in Bacillus subtilis. We report the study of biosynthesis regulation of Bacillus intermedius glutamyl endopeptidase under salt stress conditions. Salt stress during growth in medium containing 1-2.5 M NaCl, KCl or disodium succinate leads to the induction of glutamyl endopeptidase. Analysis of the regulatory region of the gene for B. intermedius glutamyl endopeptidase revealed the presence of a tentative target sequence for DegU control, AGATN10TTGAG. For the expression of the glutamyl endopeptidase gene, functional DegU protein is required. Thus, we suggest that expression of the gene for B. intermedius glutamyl endopeptidase may be controlled by a regulatory system analogous to DegS-DegU two-component system in B. subtilis.

Selection of cultivation medium for production of late stationary phase serine proteinases from Bacillus intermedius

“…Thus, addition of yeast extract into the medium for biosynthesis of late stationary phase proteinases seems not to be expedient. In accord, we have shown earlier the absence of any measurable effect of yeast extract on the intensity of B. intermedius glutamyl endopeptidase 1 biosynthesis (GABDRAKHMANOVA et al 1999). However, essential stimulating effect of this compound at concentration of 0.5% on the synthesis of subtilisin 1 was described (ITSKOVITCH et al 1995).…”

“…We have shown recently that the organic substrates, namely casein, gelatin and hemoglobin, did not influence glutamyl endopeptidase 1 synthesis by B. intermedius (GABDRAKHMANOVA et al 1999), although gelatin and casein, being present in culture medium at concentrations of 0.5-2%, activated the synthesis of B. intermedius glutamyl endopeptidase by B. subtilis recombinant strains . In this our study, the addition of gelatin or casein into the medium at concentrations of 0.1-1% led to the decrease in specific glutamyl endopeptidase 2 activity, though stimulating the growth of B. intermedius cells (Fig.…”

“…So, Staphylococcus aureus was reported not to produce proteinases in the absence of yeast extract, Mg 2+ and Mn 2+ salts as well as on the medium poor with K + (BANERJEE et al 1991). In our previous study, we have described essential stimulating effect of Ca 2+ , Mg 2+ and Co 2+ on biosynthesis of glutamyl endopeptidase 1 of B. intermedius and on the expression of the gene for this enzyme in B. subtilis recombinant strains (GABDRAKHMANOVA et al 1999. In the present work we investigated the influence of different metal ions on the subtilisin 2 and glutamyl endopeptidase 2 production by B. intermedius.…”

“…The genes coding for these enzymes are cloned, and expression in B. subtilis cells is investigated (GAB-DRAKHMANOVA et al 2002). The pathways of biosynthesis regulation of glutamyl endopeptidase also were well studied (GABDRAKHMANOVA et al 1999). Recently at the late stationary phase of growth we found two more serine proteinases in the culture filtrate of B. intermedius.…”

Genome of the halotolerant green alga Picochlorum sp. reveals strategies for thriving under fluctuating environmental conditions

“…A gene-encoding glycerol dehydrogenase is involved in the synthesis of glycerol, a common osmolyte involved in osmoregulation during salt stress. Proteases, including a glutamyl endopeptidase known to be induced during salt stress, breaks peptide bonds thereby freeing amino acids like glutamate, which may act as an osmolyte (Gabdrakhmanova et al, 2005).…”