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Collecting data on rare Mycobacterium tuberculosis ( Mtb ) clinical isolates with resistance to the new anti-tuberculosis drug bedaquiline is an important task for improving antimicrobial susceptibility testing methods. Nanopore whole genome sequencing, the proportion method on Middlebrook 7H11 medium, and BACTEC MGIT 960 assays were used to analyze genotypic and phenotypic resistance to bedaquiline. We found four mutations: atpE I66M, atpE А63Р, Rv0678 А36Т, and Rv0678 S53P in five isolates with different levels of phenotypic bedaquiline resistance., Importance: Bedaquiline (BDQ) is a new anti-tuberculosis drug. The phenotypic and genotypic data describing the mechanism of drug resistance are critical for the design of rapid and accurate diagnostic tests. We consider that our work, which describes genotypic and phenotypic resistance to BDQ, can contribute to the standardization of drug susceptibility testing., Competing Interests: The authors declare no conflict of interest.

Several disorders in the DNA structure in the cells of vertebrate and invertebrate animals, plant and algae are reviewed. Some causes of the DNA disorders, the reactive oxygen species, especially, are discussed. Some data are shown, that the common used cryoprotectants such as dimethylsulfoxide, glycerol, methanol, sucrose and albumin, are OH* scavengers. Some seldom used cryoprotectors, which scavenges several forms of active oxygen, are described. It is supposed that the antioxidant properties of the cryoprotectors are essential for their mechanism of action.

The results of research on the consequences of cryoconservation of fungi indicating the stability of their morphology are reviewed, and a number of facts indicating the changes in the properties of the fungus and the mutagenicity of cryopreservation are presented. The investigations of the last ten years confirm the Rosanov's hypothesis according to which cryoconservation must lead to an increase in the reserve of the hereditary variation of organisms.

The morphological characteristics of 35 wild plant species were studied after freezing of seeds under the conditions of deep, fast, and programmed freezing (-196 degrees C) and non-deep freezing (-10 degrees C). The seeds were stored frozen for a month. The seeds of all the species were characterized by a low humidity. The field and laboratory seed germination capacity, leaf growth, the quantity and length of shoots, the quantity of generative organs, and the variability of these characteristics were studied. It was shown that the direction of changes under different cooling conditions was the same except for the laboratory germination capacity of some species. The direction was determined by the species features rather than cooling conditions.

The possibility of long-term cryopreservation of plant objects depends on their water content. In orthodox seeds, it decreases at the late stage of maturation and is accompanied by the synthesis of protectors--sugars and proteins. These seeds easily withstand cryopreservation. Organs with a high water content, meristems, and recalcitrant seeds are dried in presence of sucrose before plunging in liquid nitrogen. In orthodox seeds, artificially dried moist seeds, and meristems, the cellular content forms glass structures that are estimated in frozen materials by differential scanning calorimetry and electron paramagnetic resonance methods. It is proposed that the glass cellular content is connected with the duration of cryopreservation. Methodical approaches to successive cryopreservation of moist plant tissues are described.

The effect of non-deep freezing (-10 degrees C) and deep freezing (-196 degrees C) on the morphological characteristics of four pink species was investigated. It was shown that the growth and development of plants after cryopreservation changed insignificantly. Rather stable characteristics (diameter of flower, the number of cauline nodes, and root length) did not change. The length of generative shoots decreased a little, and the character of histograms changed. On the other hand, the changeable characteristics (the number of vegetative shoots and flowers) decreased after seed cryopreservation. However, the number of flowers did not vary in the next year. The parameters essential for seed cryopreservation, seed germination and the quantity of fruits, did not changed. It was also found that seed freezing exerts a stimulating effect on seed germination and the top limit of some parameters, including the quantity of generative organs.

The effect of adenylic acid, glucose-6-phosphate, fructose-1,6-diphosphate and phosphoenolpyruvate on creatine kinase isoenzymes (brain extract, muscle and heart extracts and purified muscle enzyme) was studied. These effectors, especially phosphoenolpyruvate, are shown to inhibit in different degree the reaction of ATP formation catalysed by creatine kinase from all tissues. The effectors do not inhibit the creatine phosphate synthesis in extracts, but depress purified creatine kinase. The interrelationship of the creatine kinase system and the key glycolytic enzymes (phosphofructokinase, hexokinase, pyruvate kinase) is discussed.

It is shown that lactate is a noncompetitive inhibitor of muscle creative kinase Ki 16 mmol with respect to MgATP. When inhibitors are applied in combination (lactate with glucose-6-phosphate or inorganic phosphate, glucose-6-phosphate with Pi or all three inhibitors together) a competition arises. When applied together the combined action is weaker than the sum of inhibition of three effectors in the case of separate application. The competition is revealed in model experiments with metabolite concentrations peculiar to resting and acting muscle. The supposition is made that formation of lactate, glucose-6-phosphate and inorganic phosphate in the muscle tissue can induce partial, but not complete inhibition of the creatine kinase activity.

A colorimetric method is described for estimation of the adenilate kinase activity in blood serum; the method is based on coupling of adenilate- and creatine kinase reactions and on estimation of the amount of creatine formed. Adenilate kinase activity in blood serum, estimated by the method, was shown to increase 4-fold after removing of tourniquet with subsequent normalization within the next day. The same data were obtained using a spectrophotometric method for estimation of adenilate kinase based on NADP reduction in coupled reactions with hexokinase and glucose-6-phosphate dehydrogenase. An increase in creatine kinase activity in blood serum occurred later on after removing of the tourniquet; it was more distinct (8.5-fold) and maintained longer as compared with the increase in adenilate kinase activity.

Fibre bundles of glycerinated rabbit psoas muscle about 0.5-1.0 mm thick were incubated in 5 mM tris-(hydroxymethyl)-aminomethane (Tris), pH 8.0 for 5-20 hours at 4 degrees C. This treatment leads to selective removal of some proteins in the M-bands and H-zones of sarcomeres. Effects of extraction were analyzed on the basis of electron micrographs of longitudinal sections of muscle specimens, gel electrophoresis patterns of myofibrils and of the extracts, and measurements of the creatine kinase activity of myofibrils. In the X-ray diffraction patterns of the fibre bundles subjected to prolonged extraction a drastic decrease in the intensity of "442 A" and "223 A" meridional reflections and a considerably smaller decrease in the intensity of "212 A" meridional reflections were observed. The "147 A" meridional reflection remains practically unchanged. It was concluded that: (1) The reflections "442 A" and "223 A" were contributed mainly by diffraction on the minor proteins located in the central part of the thick filaments in between the C-zones. This is contrary to the widely accepted viewpoint according to which the appearance of "442 A" reflection is caused only by the C-protein component of the thick filaments. (2) The "147 A" meridional reflection is contributed mainly by C-protein and light meromyosin of the thick filaments.

Inhibition of rabbit muscle creatine kinase by lactate, glucose-6-phosphate and PEP occurs immediately and depends on the concentration of the effectors and enzyme properties. Desensitization of creatine kinase to these effectors is described. Partial desensitization to G-6-P and lactate occurs after the enzyme preincubation with dithiothreitol. A complete loss of sensitivity to lactate and a significant loss of sensitivity to G-6-P and PEP occurs after the enzyme storage at -15 degrees during several weeks. The data obtained support our previously made assumption on the allosteric regulation of the MM isoenzyme of creatine kinase.

The phenomenon of synchronism of oscillations of actomyosin and creatine kinase activity in the whole volume of the enzyme preparations was analysed. The synchronous "conformational oscillations" were observed in concentrated gels of actomyosin and in diluted actomyosin and creatine kinase solutions (ATP-creatine N-phosphotransferase, EC 2.7.3.2). The macromolecules of proteins studied may be in two or four conformational states differing enzymatic activity. Large fluctuations become possible in a range of conditions wherein two or four different states, or conformers, are equiprobable. The synchronization of conformational changes of separate macromolecules is maintained with energy derived, for instance, from some oxidative process or dilution of the solution, the process being displayed as conformational oscillations.

Using gel filtration and ultracentrifugation, the quaternary structure of muscle creatine kinase (isoenzyme MM) has been shown to depend on pH, protein concentration and ionic strength of solution. In solution the enzyme can exist not only as a dimer, but also as a monomer and tetramer with molecular weights of 40 000 and 160 000, respectively. High dilution of the protein solution and pH 6.0--5.0 provide for the monomer formation; the dimer can arise under various conditions, while the tetramer requires pH 9.0 and high protein concentration. The monomer differs from the dimer by a higher enzymatic activity, lability and needs thiol to maintain its catalytic activity. Dissociation of creatine kinase into more active subunits accounts for the increase in specific activity induced by protein dilution. It is assumed that dissociation can have physiological significance as one of the mechanisms of creatine kinase activation in muscles.

Phosphoenolpyruvate (PEP) is a potent inhibitor of muscle creatine kinase. The inhibition of ATP formation is more pronounced at pH 7.0. The substrates, creatine and creatine phosphate, partially prevent the inhibition of the enzyme activity by PEP, creatine being as an effector.

The dependence of the reaction rate on substrate concentrations at pH 8.0--7.5 does not submit the Michaelis-Menten kinetics. The dependence of v on Mg-ATP is described with a curve having an intermediate plateau. The dependence of v on the creatine concentration is expressed by a curve, which is not hyperbolic. In this case the index of the substrate concentration, (q), is variable, and it increases with the increase of creatine concentration from 1 to 2 (at the presence of effectors, PEP and ADP,--from 1 to 3.5). The specific creatine kinase activity increases 3--4-fold with protein dilution, but this effect is not observed in the presence of inhibitors to FDP and PEP. Creatine kinase is desensibilized with respect to FDP and PEP after a prolonged storage. The data obtained and the presence of an effector set indicate, that muscle creatine kinase is a regulated allosteric enzyme.

It is established that a decrease in glycogen content in liver begins at the early stages of intoxication with LG-63 and progresses with development of intoxication phenomena. Sugar content in liver and blood augments in parallel with decreasing content of glycogen in liver; concentration of ketone bodies and content of bisulfite-binding substances and pyruvic acid in liver also increase. In skeletal muscles, glycogen content was practically without changes; content of sugar, bisulfite-binding substances and pyruvic acid decreased while level of ketone bodies increased. In brain, utilization of ketone bodies decreased and in myocardium, increased.