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The article considers the pedagogical conditions for teachers to acquire physical training in the system of professional development of the necessary important qualities in the process of professional training in order to further apply the knowledge they have gained in their professional activities.

Abstract Background Zymomonas mobilis has recently been shown to be capable of producing the valuable platform biochemical, 2,3-butanediol (2,3-BDO). Despite this capability, the production of high titers of 2,3-BDO is restricted by several physiological parameters. One such bottleneck involves the conversion of acetoin to 2,3-BDO, a step catalyzed by 2,3-butanediol dehydrogenase (Bdh). Several Bdh enzymes have been successfully expressed in Z. mobilis, although a highly active enzyme is yet to be identified for expression in this host. Here, we report the application of a phylogenetic approach to identify and characterize a superior Bdh, followed by validation of its structural attributes using a mutagenesis approach. Results Of the 11 distinct bdh genes that were expressed in Z. mobilis, crude extracts expressing Serratia marcescens Bdh (SmBdh) were found to have the highest activity (8.89 µmol/min/mg), when compared to other Bdh enzymes (0.34–2.87 µmol/min/mg). The SmBdh crystal structure was determined through crystallization with cofactor (NAD+) and substrate (acetoin) molecules bound in the active site. Active SmBdh was shown to be a tetramer with the active site populated by a Gln247 residue contributed by the diagonally opposite subunit. SmBdh showed a more extensive supporting hydrogen-bond network in comparison to the other well-studied Bdh enzymes, which enables improved substrate positioning and substrate specificity. This protein also contains a short α6 helix, which provides more efficient entry and exit of molecules from the active site, thereby contributing to enhanced substrate turnover. Extending the α6 helix to mimic the lower activity Enterobacter cloacae (EcBdh) enzyme resulted in reduction of SmBdh function to nearly 3% of the total activity. In great contrast, reduction of the corresponding α6 helix of the EcBdh to mimic the SmBdh structure resulted in ~ 70% increase in its activity. Conclusions This study has demonstrated that SmBdh is superior to other Bdhs for expression in Z. mobilis for 2,3-BDO production. SmBdh possesses unique structural features that confer biochemical advantage to this protein. While coordinated active site formation is a unique structural characteristic of this tetrameric complex, the smaller α6 helix and extended hydrogen network contribute towards improved activity and substrate promiscuity of the enzyme.

The minimum residual disease (MRD) for hematopoietic and lymphoid systems tumors is an important component of patient examination during therapy. The MRD detection is performed to evaluate the effect of therapy and risk stratification during chemotherapy (acute leukemia) or at the end of it (peripheral B-cell lymphomas). The main laboratory methods for MRD assessing are molecular (polymerase chain reaction) and immunological (multi-parameter flow cytometry (FC)) methods. Immunological evaluation of MRD is the standard of clinical protocols for the treatment of childhood acute lymphoblastic leukemia during induction therapy. In the case of acute leukemia in adults, MRD assessment is usually performed at the end of the consolidation course. Clinically significant and practically standardized is the immunological assessment of MRD in B-cell chronic lymphocytic leukemia.In multiple myeloma (in World Health Organization (2016) classification – plasma cell myeloma (PCM)), work is also underway to standardize protocols and unify approaches to MRD detection. With the introduction of new drugs and treatment regimens, as well as transplantation clinical outcome of patients significantly improved and MRD value is considered as a prognostic factor. To date, the use of the MRD value as a biomarker of treatment response in PCM has been approved by the US Food and Drug Administration.With the accumulation of our knowledge regarding the MRD and to establish the clinical significance of the FC in PCM, International Multiple Myeloma Study Group (IMWG) in 2011 was added the following definition to the traditional criteria of PCM complete remission: “Immunophenotypic complete remission” – the immunophenotypically absence of aberrant clonal plasma cells in the bone marrow when analyzing at least 1 million myelocaryocytes using a multiparameter FC (4 or more parameters).This article discusses the evolution of immunological approaches using a multi-parameter FC to detect MRD in patients with PCM in accordance with various existing protocols, features of the preanalytical stage and general rules for FC detection of MRD in PCM.

The subject of research in the article are algorithms for fast calculation of autoregression coefficients in digital spectral analysis and estimation of the number of arithmetic operations required for their implementation. The aim of the article – comparative analysis of the speed of different algorithms for calculating the coefficients of autoregression as part of the algorithms of spectral analysis, including analysis of the complexity of their microcontroller implementation. Tasks to be solved: selection of spectral analysis methods suitable for diagnostics of technological equipment, analysis of methods for calculating autoregression coefficients and derivation of relations for estimating software complexity of algorithms and calculation of numerical estimates of addition and multiplication for some algorithms, adaptation of developed methods and estimates to microcontrollers. spectrum Applied methods: algorithm theory, Fourier transform, natural series, microcontroller programming. The results obtained: it is shown that spectral estimation methods based on Yul-Walker equations, which require the calculation of autoaggression coefficients, combine sufficient resolution and resistance to interference with acceptable implementation complexity. Estimates of the number of additions and multiplications for the Levinson, Durbin, and Trench algorithms are obtained, and their comparative analysis is performed. The calculation times for microcontroller arithmetic with fixed and floating points were count upon. Conclusions: When constructing spectrum analyzers for the diagnosis of technological equipment, it is advisable to use the Yul-Walker method. A comparison of Levinson, Durbin, and Trench algorithms for calculating autoregression coefficients showed that the Trench method requires a minimum number of additions, and the Durbin method requires a minimum number of multiplications. At microcontroller realization of spectrum analyzers, it is necessary to consider features of the arithmetic used by the controller. The Trench method is the fastest in the case of floating-point arithmetic and small-scale modeling. In other cases, Durbin's method is more effective.