Instability of waves formed by motile bacteria

Abstract Cell-free enzyme preparations of the obligately anaerobic halophilic eubacterium Haloanaerobium praevalens synthesize fatty acids from malonyl-CoA. The reaction is stimulated by NaCl and KCl at a concentration of 1 M, and only slightly inhibited by salt concentrations as high as 3 M. Thus, the fatty acid synthetase of H. praevalens is expected to the fully active at the high intracellular salt concentrations present, and it is the first fatty acid synthetase reported to be active in the presence of high salt concentrations.     

Effect of a biostimulant formed by yeastlike fungi on the dynamics of the accumulation of CoA, biotin and levorin in the process of growth of S. levoris

Regularities of the effect of a biostimulator produced by years-like fungi on accumulation of CoA, biotin and levorin in a developing culture of S. levoris were studied. It was shown that addition of the biostimulator to the fermentation medium resulted in increased accumulation of CoA and biotin in the mycelium of the levorin-producing culture within the first 48 hours of the growth and in their more intensive consumption at the final stages of the fermentation process. The rate of the levorin synthesis in the medium with the biostimulator markedly exceeded that in the control.     

Intratumor heterogeneity: Nature and biological significance

Intratumor heterogeneity inherent in the majority of human cancers is a major obstacle for a highly efficient diagnosis and successful prognosis and treatment of these diseases. Being a result of clonal diversity within the same tumor, intratumor heterogeneity can be manifested in variability of genetic and epigenetic status, gene and protein expression, morphological structure, and other features of the tumor. It is most likely that the appearance of this diversity is a source for the adaptation of the tumor to changes in microenvironmental conditions and/or a tool for changing its malignant potential. In any case, both processes result in the appearance of cell clones with different undetermined sets of hallmarks. In this review, we describe the heterogeneity of molecular disorders in various human tumors and consider modern viewpoints of its development including genetic and non-genetic factors of heterogeneity origin and the role of cancer stem cells and clonal evolution. We also systematize data on the contribution of tumor diversity to progression of various tumors and the efficiency of their treatment. The main problems are indicated in the diagnosis and therapy of malignant tumors caused by intratumor heterogeneity and possible pathways for their solution. Moreover, we also suggest the key goals whose achievement promises to minimize the problem of intratumor heterogeneity and to identify new prognostic, predictive, and target markers for adequate and effective treatment of cancer.     

New heptaene antibiotic, flavomycin, formed by Act. flavus var. geptinicus var. nov]

An actinomycetous culture LIA-0734 was isolated from a soil sample. By its morphologo-cultural properties it was close to Act. flavus and differed from the latter in the sporophores, colour of the substrate mycelium on synthetic media amd markedly pronounced antagonism with respect to yeasts and yeast-like fungi. The culture was classified as Act. flavus var. geptinicus var. nov. The actinomycete produced new aromatic heptaens: flavomycins A and B. Their physico-chemical and biological characteristics and singularity are presented.