Том 55, № 7 (2019)

The creation and development of genome editing (GE) technologies bring new opportunities for the genetic engineering of farm mammals and poultry. The present review characterizes GE systems based on ZFN, TALEN, and CRISPR/Cas9 and directions for their improvement in relation to farm animals. The fields for the application of GE technologies in animal husbandry and poultry farming and the objectives and prospects for their further development are discussed.

An1 original drug, Glypin, has been developed for the treatment of type-II human diabetes mellitus. Its active pharmaceutical substance is a completely biosynthetic, recombinant, modified, human glucagon-like peptide (rmGlp-1) obtained via culturing of E. coli cells. In addition to the GLP-1 portion, which contains the well-known Ala8Gly substitution, the rmGLP-1 protein has an additional amino acid sequence at the C-terminus that includes the heparin-binding peptide of human HB-EGF. Preclinical testing of Glypin specific activity (with Lixumia as a reference drug) was performed. A commercial preparation of Lixumia served as the main reference drug for comparison with the specific activity of Glypin. During preclinical studies of both medicines, it was shown that Glypin and Lixumia have similar mechanisms, power, and time of action upon subcutaneous and intramuscular introductions, as well as comparable therapeutic effects under long-term use. Based on these data, the subcutaneous injection was selected as the main therapeutic method of Glypin administration; the minimal effective dose for Glypin preclinical study was established as 100 μg/kg body mass, and a single dose for human treatment was defined as 0.75 and 1.5 mg. The intranasal introduction of Glypin was observed to have a statistically reliable positive effect on the cognitive capacities of a mouse with Alzheimer’s disease model. The similarity of the characteristics of Glypin and Lixumia shown in our study make it possible to expect that they will have equal therapeutic efficacy with daily use of a single dose.

In¹ order to increase the expression level of gene for recombinant phytase in Pichia pastoris, a synthetic sequence of the phyOp-mod gene, which encodes phytase from Obesumbacterium proteus, has been designed and optimized by its codon composition. The GC content was adjusted to 48.33%, and AT-rich segments were eliminated. The main characteristics for the purified enzyme are established. The optimal pH and temperature values for РhyOp phytase functioning prove to be 4.0 and 50°C, respectively. The specific activity, Michaelis constant (Km), and maximal rate of reaction (V_max) with sodium phytate as a substrate are 1452 U/mg, 0.31 mM, and 823 U/mg, respectively. It is shown that optimization of the codon composition increased the expression of the target product gene. The recombinant phytase designated as PhyOp demonstrated great potential for application as a feed additive due to its relatively high specific activity and good kinetic characteristics.

The processes of oxidative depolymerization and acidic hydrolysis have consistently been used for the pretreatment of lignocellulosic biomass (wheat straw, sawdust, and lignin), which makes it possible to obtain a high content of soluble organic compounds in the hydrolysate (44–94 g COD/L) and to enhance the concentration of reducing sugars from 1 to 36%. The introduction of Clostridium acetobutylicum bacteria to an acidogenic biocatalyst resulted in an even greater increase in the content of volatile fatty acids and ethanol in the end product. The maxima among the studied substrates yields of butyric acid and ethanol were observed when the pretreated straw was hydrolyzed (27% (0.82 g/L) and 17.4% (0.44 g/L), respectively). It was shown that the addition of glycerol as a substrate makes it possible to increase the yields of butyric and acetic acids as a result of the conversion of the pretreated biomass; the addition of glycerol to straw in a 1 : 1 ratio enhanced the maximum butyric acid and VFA yields up to 32% (0.96 g/L) and 72% (2.67 g/L), respectively.