Molecular and genetic features of trichinella isolates of the Central Chernozem region

The purpose of the research is to study the taxonomic affiliation and haplotypic diversity of trichinella isolates circulating in the Voronezh Nature Reserve and adjacent territories of the Central Chernozem region using modern molecular genetic methods and data from the International Information Database (NCBI).

Materials and methods. The larvae of Trichinella nativa isolated from frozen muscle tissue of wild and domestic animals were used as the studied material. The material was collected from those who died in the Voronezh Nature Reserve and in adjacent territories during regulatory measures and regulated hunting, as a result of poaching and those who died on highways. Muscle tissue samples from wild and domestic predatory mammals with diagnosed trichinella infestation were also used, recorded in 70% ethanol and 10% formalin. Native DNA was isolated from the obtained larvae, followed by Multiplex PCR (MT PCR) for primary species identification. The native DNA samples identified by MT PCR were amplified with primers 37F_Tri and 42R_Tri to study the mt DNA fragment of cytochrome C oxidase subunit 1 (cox1). The obtained amplicons were sequenced by Sanger and deposited in the GenBank NCBI international database.

Results and discussion. The presented results of molecular genetic studies confirm the previously presented data on the taxonomic affiliation of Trichinella – T. nativa (Romashov et al., 2006). Bioinformatics analysis of four deposited nucleotide sequences showed the presence of three single-nucleotide substitutions in the cox1 gene region of T. nativa. The two substitutions are synonymous and do not affect the process of transcription and subsequent translation, since in both cases the same amino acid, valine, is encoded. However, there is a single nucleotide substitution at position 67 in T. nativa (a sample from a common lynx, GenBank №PX624076) leads to the encoding of another amino acid, methionine, which can significantly affect protein biosynthesis and, as a result, alter the physiological properties of the parasite.

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