Characterization of alkaline protease produced byStreptomyces griseorubensE44G and its possibility for controllingRhizoctoniaroot rot disease of corn

Abstract

The antifungal activity of Streptomyces griseorubens E44G against Rhizoctonia solani, the causal agent of root rot disease of corn, was investigated. The mycelial growth of R. solani was inhibited by S. griseorubens E44G, indicating that it has an antifungal potential. The antagonist, S. griseorubens E44G, was detected to have proteolytic activity, using the method of casein hydrolysis. Moreover, the protease production was optimized under submerged conditions. The purification and precipitation of protease were achieved by ammonium sulphate and Sephadex G-100 gel filtration chromatography. Protease activity was detected spectrophotometrically based on the production of tyrosine. The molecular weight of the enzyme (35 kDa) was determined by sodium dodecyl sulphate polyacrylamide gel electrophoresis . The optimum activity of the enzyme was detected at pH 8.5 and 60 C. The results indicated that the enzyme was thermostable and retained full activity even after 1 hour of incubation at 60 C. The purified enzyme substantially inhibited the growth of R. solani, indicating that this enzyme may be actually involved in the antagonistic process.

Effects of Plant Growth Promoting Rhizobacteria (PGPR) on <i>In Vitro</i> Bread Wheat (<i>Triticum aestivum</i> L.) Growth Parameters and Biological Control Mechanisms

“…Few or most of these factors attribute an advantage to treated plants. The potential use of actinomycetes isolates as a biocontrol agent has been reviewed previously [38] [39], where inoculation with these microorganisms promoted the growth of plants. Almost all rhizospheric actinomycetes isolate enhanced the agronomic performance of wheat cultivar, Hidhab (HD) by influencing its growth parameters.…”

“…The fungicide has a detrimental effect on leaves number increase and root length; while biological control against the pathogen by different actinomycetes isolates especially D5 and D8 is a more best to fight against diseases in bread wheat (HD) variety (Figure 5(a): A1, A2 & Figure 5(b): B1, B2). Production of antifungal substances [35] [36] and phytohormones [35]- [37] by actinomycetes isolates, can increase seed germination and controlling plant pathogenicity [38] [39]. Few or most of these factors attribute an advantage to treated plants.…”

Isolation and characterization of rhizospheric Streptomyces spp. for the biocontrol of Fusarium wilt (bayoud) disease of date palm (Phoenix dactylifera L.)

“…Characters like cell wall degradation have been heavily reported as important mechanisms of antifungal action for various Streptomyces species (Froes et al, 2012;Sadeghy and Hatamy, 2014;Al-Askar et al, 2015;Sabaratnam and Traquair, 2015). In this study, the production of fungal cell walldegrading enzymes was examined because this is an important mechanism of fungal inhibition for PGPR agent.…”

“…A collective effect of many factors, such as production of antifungal substances (Li et al, 2011;Souaghi et al, 2015) and phytohormone (Li et al, 2011;Souaghi et al, 2015;Spaepen and Vanderleyden, 2011) by Steptomyces spp. strains, might be involved in increasing seed germination and controlling plant pathogenicity (Al-Askar et al, 2015;Sbaratnam and Traquair, 2015).…”

Comparison across growth kinetic models of alkaline protease production in batch and fed-batch fermentation using hybrid genetic algorithm and particle swarm optimization

“…[2] They are widely used in the tanning industry, in the manufacturing of biological detergents, meat tenderization, peptide synthesis, food industry, pharmaceutical industry, and in bioremediation processes. [3] Microbial proteases are gaining more importance than conventional chemicals that cleave peptides because of the cheaper production cost and use of renewable resources. [4] Among all protease-producing microbial systems, microbes belonging to the Bacillus genus have gained importance because of extracellular enzyme production under submerged fermentation conditions.…”