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Beta-1,3-1,4-glucanase has been applied in the brewing and animal feed additive industry. It can effectively improve digestibility of barley-based diets and reduce enteritis. It also reduces viscosity during mashing for high-quality brewers malt. The aim of this work is to clone beta-1,3-1,4-glucanase-encoding gene and express it heterogeneously. The gene was amplified by polymerase chain reaction using Bacillus licheniformis genomic DNA as the template and ligated into the expression vector pET28a. The recombinant vector was transformed into Escherichia coli. The estimated molecular weight of the recombinant enzyme with a six-His tag at the N terminus was about 28 kDa, and its activities in cell lysate supernatant were 1,286 and 986 U ml(-1) for 1% (w/v) barley beta-glucan and 1% (w/v) lichenan, respectively. Accordingly, the specific activities were 2,479 and 1,906 U mg(-1) for these two substrates. The expression level of recombinant beta-1,3-1,4-glucanase was about 60.9% of the total protein and about 12.5% of the total soluble protein in crude cell lysate supernatant. Acidity and temperature optimal for this recombinant enzyme was pH 5.6 and 40 degrees C, respectively.

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Rice blast and bacterial blight are important diseases of rice (Oryza sativa) caused by the fungus Magnaporthe oryzae and the bacterium Xanthomonas oryzae pv. oryzae (Xoo), respectively. Breeding rice varieties for broad‐spectrum resistance is considered the most effective and sustainable approach to controlling both diseases. Although dominant resistance genes have been extensively used in rice breeding and production, generating disease‐resistant varieties by altering susceptibility (S) genes that facilitate pathogen compatibility remains unexplored. Here, using CRISPR/Cas9 technology, we generated loss‐of‐function mutants of the S genes Pi21 and Bsr‐d1 and showed that they had increased resistance to M. oryzae. We also generated a knockout mutant of the S gene Xa5 that showed increased resistance to Xoo. Remarkably, a triple mutant of all three S genes had significantly enhanced resistance to both M. oryzae and Xoo. Moreover, the triple mutant was comparable to the wild type in regard to key agronomic traits, including plant height, effective panicle number per plant, grain number per panicle, seed setting rate, and thousand‐grain weight. These results demonstrate that the simultaneous editing of multiple S genes is a powerful strategy for generating new rice varieties with broad‐spectrum resistance.

In this study, magnetic carbonaceous acids were synthesized by pyrolysis of the homogeneous mixtures of glucose and magnetic Fe3O4 nanoparticles, and subsequent sulfonation. The synthesis conditions were optimized to obtain a catalyst with both high acid density (0.75 mmol g−1) and strong magnetism [magnetic saturation, Ms = 19.5 Am2 kg−1]. The screened catalyst (C-SO3H/Fe3O4) was used to hydrolyze ball-milled cellulose in a microwave reactor with total reducing sugar (TRS) yield of 25.3% under the best conditions at 190 °C for 3.5 h. It was cycled for at least seven times with high catalyst recovery rate (92.8%), acid density (0.63 mmol g−1) and magnetism (Ms = 12.9 Am2 kg−1), as well as high TRS yield (20.1%) from the hydrolysis of ball-milled cellulose. The catalyst was further successfully tested for the hydrolysis of tropical biomass with high TRS and glucose yields of 79.8% and 58.3% for bagasse, 47.2% and 35.6% for Jatropha hulls, as well as 54.4% and 35.8% for Plukenetia hulls.

The short-chain FOSs with high purity were prepared using a two-step strategy: Aspergillus japonicus extracellular beta-fructofuranosidase-catalyzed synthesis of FOSs followed by cultivation with Pichia pastoris (P. pastoris). The higher FOSs content was obtained after 8 h under the catalysis of beta-fructofuranosidase at pH 5.5 and 55 degrees C. Successive P. pastoris cultivation exhausts almost all monosugars in 12 h at 30 degrees C, which increases the purity of FOSs, and also recovers beta-fructofuranosidase activity by ceasing the inhibition of glucose from catalysis of the enzyme, yielding more FOSs. Finally, the FOSs purity was increased from 56.55 to 84.45% (26.47% 1-kestose and 57.98% nystose).

Karyotypic analysis of plaice, Pleuronectes platessa L., and cod, Gadus morhua L., revealed that the chromosome numbers in both species vary but that chromosome arm numbers (NF) stay constant. The C-, Q-and R-banding patterns also confirmed that the population of plaice studied shows Robertsonian polymorphism. The tendency of reduction in chromosome number in fishes suggests that Robertsonian fusions play a role in karyotype evolution in fishes.