Glycogen, a major reservoir of energy in Saccharomyces cerevisiae, is found to be present as soluble and membrane-bound insoluble pools. Yeast cells can store excess glycogen when grown in media with higher concentration of sugar or when subjected to nutritional stress conditions. Saccharomyces cerevisiae NCIM-3300 was grown in media having ethanol concentrations up to 12% (v/v). The effects of externally added ethanol on glycogen and other carbohydrate content of yeast were studied by using alkali digestion process. Fermentative activities of cells grown in the presence of various ethanol concentrations (2-8% v/v) exhibited increase in values of glycogen and other carbohydrate, whereas cells grown with higher concentrations of ethanol (10-12% v/v) exhibited depletion in glycogen and carbohydrate content along with decrease in cell weight. Such inhibitory effect of ethanol was also exhibited in terms of reduction in total cell count of yeast grown in media with 2-16% (v/v) ethanol and 8% (w/v) sugar. These data suggest that, as the plasma membrane is a prime target for ethanol action, membrane-bound insoluble glycogen might play a protective role in combating ethanol stress. Elevated level of cell-surface alpha-glucans in yeast grown with ethanol, as measured by using amyloglucosidase treatment, confirms the correlation between ethanol and glycogen.

Objective: The main objective of the study was isolation, purification and characterization of protein protease inhibitor from the seeds of Phaseolus vulgaris and analysis of its antimicrobial potential. Methods:The protease inhibitor was extracted by homogenizing seeds of Phaseolus vulgaris in 0.1 M phosphate buffer (pH-7.0). The crude extract of the inhibitor was purified by using ammonium sulphate precipitation followed by DEAE Cellulose ion exchange chromatography. The protease inhibitor was characterized to determine its optimum pH and pH stability, optimum temperature and temperature stability, stability in the presence of chemical modifiers, thermal stabilizers, metal ions, detergents, oxidising and reducing agents. The antimicrobial potential of the inhibitor against various bacterial species was confirmed using agar well diffusion method. Results:The extracted protease inhibitor was purified to homogeneity with a 1.4 fold increase in the specific activity and 56 % purification yield. Inhibitor was optimally active at pH 7.0 and a temperature of 50 °C as well as showed considerable stability over pH ranging from 4.0-11.0 and up to a temperature of 70 °C for 4 h duration. The inhibitor was substantially active and stable in the presence of surfactants 1 % (v/v) Tween 20, 4 % (v/v) of oxidizing agents such as dimethyl sulphoxide (DMSO) and hydrogen peroxide (H2O2), 0.8 % (v/v) of reducing agents β-mercaptoethanol and Sodium thioglycolate. Metal ions Mg ++ , Ca ++ and Zn ++ enhanced the activity of inhibitor while CaCl2, glycine and glycerol promoted thermal stability of the inhibitor. Chemical modification of amino acids at the active site by diethyl pyrocarbonate (DEPC) and phenyl methyl sulphonyl fluoride (PMSF) led to decrease in the inhibitory activity. The stoichiometry of trysin-protease inhibitor interaction was 1:2 while 216 μg of the inhibitor effected 50 % inhibition. The inhibitor displayed antimicrobial activity against Aeromonas hydrophilla, Citrobacter freundii and Acinetobacter baumanii. Conclusion:The experimental results confirmed the anti proteolytic action of protease inhibitor extracted from P. vulgaris as well as its promising antimicrobial properties. Thus isolated protease inhibitor has significant industrial and therapeutic potential.

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The genome of Ignatzschineria sp. strain RMDPL8A was sequenced and analyzed. This draft genome sequence was 2,175,527 bp long, with a GC content of 45.12% and 1,890 protein coding genes.