Alkyl Sulfatase of Cholera Vibrios

The aim of the work was to study the structure of the alkyl sulfatase (asu) gene in Vibrio cholerae strains of various serogroups, as well as to compare nucleotide and amino acid sequences of alkyl sulfatases using various methods of bioinformatic analysis.Materials and methods. 483 strains of V. cholerae O1, O139 and nonO1/nonO139 serogroups were employed in the work. The search for the gene, its recurrence, and localization was carried out applying the Blast software. The nucleotide and corresponding amino acid sequences of the gene, as well as its structure, were studied using bioinformatic analysis. Sequencing was performed on the MiSeq (Illumina) platform. The enzymatic activity was detected using a medium, confirming the presence/absence of the gene by PCR in vitro and in silico.Results and discussion. Bioinformatic analysis of the nucleotide and corresponding amino acid sequences of the asu gene has been carried out and its structure investigated. Four functional domains have been identified. In the beta-lactamase domain, a conservative amino acid sequence -HAHADH- has been found in all strains of cholera vibrios, which is part of the Zn2+ binding motif. It has been established that the alkyl sulfatase of cholera vibrios belongs to the family of Zn2+-dependent β-lactamases. Blast analysis has revealed the similarity of nucleotide and amino acid sequences of alkyl sulfatases in representatives of V. cholerae O1 and O139 serogroups (ctxAB+tcpA+) and representatives of the genera Aeromonas and Pseudomonas, which is in the line with the data of 3D modeling of the amino acid sequence structures of the alkyl sulfatase enzyme in these microorganisms. The bioinformatic analysis of nucleotide and amino acid sequences of alkyl sulfatases in cholera vibrios has showed the conservativeness of these sequences in toxigenic strains and the presence of a number of single mutations in the asu gene in atoxigenic ones. The presence or absence of the asu gene has been established by PCR in vitro and in silico and confirmed by the results obtained using the Blast program. It is demonstrated that the presence/absence of the asu gene correlates with the ability/inability of O139 strains to hydrolyze SDS on the medium. These results can be used in studying mechanisms of cholera vibrios adaptation, persistence and pathogenicity

HISTORY AND DEVELOPMENT DIRECTIONS OF INDUCTION HEATING HFC AT THE MINSK AUTOMOBILE PLANT

The data on the development of induction technology in the Republic of Belarus on the example of the Minsk Automobile Plant are given. Their development began at the end of the fifties at the Minsk Tractor Plant, and the highest development has been obtained at the Minsk Automobile Plant from 1983 to 2008. The short features of energy-efficient processes created at MAZ in collaboration with country’s institutions are given: surface hardening on the contour of gear wheels, a body-surface-hardened gears and satellites, the impulse hardening of complex configuration, the heat treatment of long items and bulk materials, etc.Литератур

Changing the spectrum of fatty acids as one of the mechanisms of adaptation/persistence of microorganisms

The review presents the basic information available in the literature on changes in the composition of fatty acids in various microorganisms in response to various environmental factors (stressors). The issues affecting the importance of fatty acids as biomarkers of pathogenetic and adaptive-persistent potential of bacteria are discussed. The prospects of studying the spectrum of fatty acids in the field of biochemistry, in particular, lipidomics of infectious diseases are noted

Public health services: implementation of healthcare technologies

This paper summarizes the arguments and counterarguments within the scientific discussion on the factors that influence public health service. The main purpose of this research is to determine the expected indicators of pathogenic and sanogenic effects on significant risk factors of pathology among children. For achieving the research goal, the authors substantiated the models of final results for the modification of risk factors. Investigation of antenatal and genealogical factors in healthy and ill children groups was performed using a specially compiled expert assessment card and parents’ interviews

Identification of microorganisms using gas chromato-massspectrometry

The review presents the basic information available in literature on the use of gas chromatography-massspectrometry. Issues concerning the significance of this method for the identification of microorganisms are discussed. The prospects of creating domestic software and databases of mass spectra of microorganisms are noted

TECHNIQUE OF QUALITY CONTROL OF STRUCTURE OF TOOTH GEARS OF THE MOTOR AND TRACTOR MACHINERY TRANSMISSIONS

The reactant for microstructure quality assurance of cemented layer and a core of transmissions gears of the motor and tractor technique, enabling to reveal and identify the structural components influencing working capacity of details, is offered

INFLUENCE OF THE THERMAL PROCESS STAGE ON THE SIZE OF VALID GRAIN OF CONSTRUCTIONAL CARBURIZED STEEL GRADE 20CHN3A

Results of studies of the kinetics of changes in actual grains during technological process at different stages of the manufacture of parts with the use of a universal metallographic etchant to identify borders of valid grains in rolling and stamping in carburizing layers and core parts made of alloy structure steel grades are presented

STRUCTURAL FEATURES OF ECONOMICALLY-ALLOYED STEEL 20HGNMB AFTER CHEMICAL AND THERMAL HARDENING

It is established that structural characteristics of the parts produced of industrial steel melting correspond to the requirements rendered to quality of the cemented layer and core of high-intense gear wheels according to the results of spectral, metallographic, X-ray structural and durometric analyses

Cholera Vibrio Membrane Protein <I>OmpT</I> as an Omptin Belonging to <I>Vibrionaceae</I> Family

Concerned are the issues related to enterobacteria omptins, their structure and functionality, as well as alternative role in pathogenesis of the infections induced by them. Isolated from cholera vibrio, and later purified using differential centrifugation and column chromatography has been porin protein of the OmpT outer membranes, with the molar mass of approximately 40 kDa. Synthesis of porin is under control of the complex regulatory system. It does not contain cysteine, but possesses proteolytic activity with broad substrate specificity: it hydrolyzes fibrin, protamin, gelatine; transduces human plasminogen into plasmin, which provides for the well-known advantages for the vibrios in the intestine of a susceptible host. Comparative computer-assisted analysis of amino acid sequence has revealed that cholera vibrio OmpT protein relates to the omptins of enterobacteria as a far-remotely one, and has 13 % identity and similarity to it. OmpT protein is probably affiliated to a new class of porins of the family Vibrionaceae