Improvement of bread making quality by supplementation with a recombinant xylanase produced by Pichia pastoris

Abstract

Xylanases (EC 3.2.1.8) are hydrolytic enzymes, which randomly cleave the β-1,4-linked xylose residues from xylan. The synthetic gene xynBS27 from Streptomyces sp. S27 was successfully cloned and expressed in Pichia pastoris. The full-length gene consists of 729 bp and encodes 243 amino acids including 51 residues of a putative signal peptide. This enzyme was purified in two steps and was shown to have a molecular weight of 20 kDa. The purified r-XynBS27 was active against beechwood xylan and oat spelt xylan as expected for GH 11 family. The optimum pH and temperature values for the enzyme were 6.0 and 75 °C, respectively. The Km and Vmax were 12.38 mg/mL and 13.68 μmol min/mg, respectively. The r-XynBS27 showed high xylose tolerance and was inhibited by some metal ions and by SDS. r-XynBS27 was employed as an additive in the bread making process. A decrease in firmness, stiffness and consistency, and improvements in specific volume and reducing sugar content were recorded.

Rahnella sp., a Dominant Symbiont of the Core Gut Bacteriome of Dendroctonus Species, Has Metabolic Capacity to Degrade Xylan by Bifunctional Xylanase-Ferulic Acid Esterase

“…Similar values of K m have been reported for xylanase Xyl1 produced by the fungus Penicillium chrysogenum P33 ( K m of 9.6 mg ml –1 ) using beechwood xylan as substrate ( Yang et al, 2019 ) and in Streptomyces sp. S27 where the K m value was 12.38 mg ml –1 ( de Queiroz Brito Cunha et al, 2018 ).…”

Potential applications of extracellular enzymes from Streptomyces spp. in various industries

“…). Hydrolyzed hemicellulose comes in compact bonding with water in the dough, which results in decreasing the dough firmness, increasing volume, and creating finer and more uniform crumbs(Brito Cunha et al 2018). Brito Cunha et al (2018 improved quality of bread with supplementation of recombinant xylanase produced from xynBS27 of Streptomyces sp.…”