Significance of location of enzymes on their release during microbial cell disruption

Abstract

The release kinetics of the enzyme invertase and alcohol dehydrogenase from yeast and penicillin acylase from E. coli during disruption using various techniques has been investigated. The disruption techniques used were sonication, high-pressure homogenization, and hydrodynamic cavitation. The first-order-release kinetics was applied for the determination of release rate of these enzymes and total soluble proteins. Location factor (LF) values were calculated using these release rates. The location of the enzymes as given by the values of location factor coincided well with those reported in the literature. Varying values of location factor for the same enzyme by different disruption techniques gave some indications about the selectivity of release of a target enzyme by different disruption techniques. Varying values of location factor for the same enzyme with the use of a particular equipment or disruption technique at different conditions reveals the degree to which the cell is disrupted. Few plausible applications of this location factor concept have been predicted and these speculations have been examined. This location factor concept has been used for monitoring the heat-induced translocation of ADH and location of penicillin acylase during the growth period of E. coli cells.

Influence of micronutrients on yeast growth and β-d-fructofuranosidase production

“…CaCl 2 at -level (lower concentration) and MnSO 4 at +level (higher concentration) will result in higher enzyme production than when either used alone at those levels. Increasing the concentrations of KH 2 PO 4 had a sharp increase in enzyme production compared to that of MnSO 4 . Enzyme production was observed to be more when these two variables were used at higher concentrations (Fig.…”

“…Analysis of the data indicates that six variables, i.e. KH 2 PO 4 , CaCl 2 , MnSO 4 , Na 2 MoO 4 , ZnSO 4 and CoCl 2 had signifi cant effect on enzyme production with 'P' value <0.05 (Table 3). However the effect of CaCl 2 and Na 2 MoO 4 was negative indicating that they had inhibitory effect at higher concentrations and should be used at the lower level (-1).…”

“…Furthermore, zinc ions are thought to have some effects on stability and dynamics of cell membranes, which may lead to downstream effects on cell permeability and signaling systems [21]. Other variables MgSO 4 , NaCl, CuSO 4 and KI had no signifi cant effect either on yeast growth or its FFase production (Table 3). MgSO 4 had no effect on FFase production at both the levels studied, while increasing the concentration of CoCl 2 lead to an increase in enzyme production.…”

“…It is used for the manufacture of calf feed and food for honeybees [2,3]. FFase also has its application as a sensor for continuous sucrose determination [4].…”

Probing the bioeffects of cavitation at the single-cell level

“…Enzyme and protein can be selectively released [4], depending on their location in the cell, periplasm or cytoplasm [5].…”