Purification and characterization of a xylanase from Bacillus subtilis isolated from the degumming line

Abstract

Xylanases catalyze the hydrolysis of xylan, a major hemicellulose component of cell wall besides cellulose in most plant species. To extract cellulose fibers, it will be invaluable to screen for more effective xylanase-producing microorganisms. In this paper a new strategy for easy screening of xylanase-producing strains from the degumming line was presented. Using this strategy, a weak-acidic, cellulase-free xylanase from Bacillus subtilis has been isolated, purified and characterized. The xylanase showed high specific activity (36,633.4 U/mg), presented stable characteristics and can be separated and purified simply, with molecular weight 23.3 kD, pI 9.63. It reached its optimal activity at pH 5.8 and 60 °C, and retained over 80% of its maximal activity after pre-incubation at temperature 60 °C or pH 4.6 ~ 6.4. Also, a two-step purification procedure based on the combination of ultrafiltration and gel filtration chromatography was introduced and described, achieving 17-fold purification with 68.11% yield.

Secretory expression and characterization of xylanase isolated from Bacillus subtilis E20 increase the utilization of plant ingredients in tilapia feed

“…The mature polypeptide of BsXynE20 consisted of 185 amino acid residues with a predicted molecular weight of 20.25 kDa and a pI value of 9.11; these values were similar to xylanase belonging to other strains of B. subtilis (Banka et al, ; Guo et al, ; Khandeparker, Verma, & Deobagkar, ). The calculated size of BsXynE20 was closely matched with the approximate‐20‐kDa band in SDS‐PAGE and Western blot analysis, and enzyme activity was confirmed by zymogram analysis.…”

“…The recombinant xylanase produced by B. subtilis RIK1285 performed optimally in sodium citrate buffer between pH 5.0 and pH 6.0; however, many recombinant xylanases from other strains of B. subtilis have shown that a pH value of approximately 6.0 is optimal for enzyme activity (Banka et al, ; Huang et al, ; Jalal, Rashid, Rasool, & Akhtar, ). By contrast, native xylanases purified from other strains of B. subtilis have performed optimally between pH 5.0 and pH 6.0 (Guo et al, ; Khandeparker et al, ). This difference may result from the host ( Escherichia coli ) employed for recombinant protein expression.…”

“…Under the assay conditions used in our study, recombinant BsXynE20 demonstrated optimal activity at 60°C while retaining over 50% relative activity between 45 and 68°C. In contrast to other xylanases of B. subtilis R5 (Jalal et al, ) and B. subtilis B10 (Huang et al, ), recombinant BsXynE20 has a higher optimal temperature that renders it highly similar to the xylanases of B. subtilis CXJZ (Guo et al, ) and B. subtilis cho40 (Khandeparker et al, ). The thermostability experiment in the present study indicated that in the absence of substrate, recombinant BsXynE20 was extremely sensitive to temperatures higher than 50°C.…”

Biochemical properties of a new thermo- and solvent-stable xylanase recovered using three phase partitioning from the extract of Bacillus oceanisediminis strain SJ3

“…3a, for 10 min reaction the optimum temperature was 55 °C (assayed in the range 20–100 °C), the xylanase produced by Bacillus brevis is also optimally active at the same temperature (Goswami et al 2013). The optimum temperature of the enzyme is near to that of the xylanases from B. subtilis strain CXJZ isolated from the degumming line (60 °C) (Guo et al 2012) and Bacillus sp. strain 41M-1 which showed maximum activity at 50 °C (Nakamura et al 1995) and Bacillus sp.…”

Bacterial succession and metabolite changes during flax (Linum usitatissimum L.) retting with Bacillus cereus HDYM-02

“…Pectin and hemicellulose are the main gummy substances present in the straws of fiber plants, which can be degraded by the degumming enzymes produced by microbes such as pectinolytic bacteria1044, and mannanase- and xylanase-producing bacteria4546. Afterwards, the presence of galacturonic acid and reducing sugars, which are residues of gummy substances, can indicate the degumming extent474849.…”