Enzyme excretion

IV. PARASITISM. Lysis by hydrolytic enzymes excreted by microorganisms is a well-known feature of mycoparasitism. Chitinase and P-l,3 glucanase (laminarase) are particularly important enzymes secreted by fungal mycoparasites capable of degrading the fungal cell wall components, chitin, and P-1,3 glucan (131-134). 

Enzyme Excretion During Wood Cell Wall Degradation by Phanerochaete chrysosporium... 

JOSELEAU ruel Enzyme Excretion During Cell Wall Degradation 445... 

JOSELEAU RUEL Enzyme Excretion During Cell WaU Degradation 449... 

The phenomenon is well-known20 and correlates with the accumulation of /M,3 glucanases and chitinases, the cell wall degrading enzymes excreted by some fungi. Chemicals that promote SAR are potential... 

Ellis, B.G. Price, R.G. (1975) Urinary enzyme excretion during renal papillary necrosis induced in rats with ethyleneimine. Chem.-biol. Interact., 11, 473-482... 

Most enzymes of industrial importance like amylase, protease, cellulase, etc. are extracellular. By the addition of surface-active agents, enzyme excretion through cell membranes and consequently the yield of these enzymes can be increased 38). Extracellular enzymes are separated from microbial cells by filtration and, if necessary, in addition by enrichment. Intracellular enzymes are released by disruption of the cells... 

Gossett KA, Turnwald GH, Kearney MT et al. (1987) Evaluation of gamma-glutamyl transpeptidase-to-creatinine ratio from spot samples of urine supernatant, as an indicator of urinary enzyme excretion in dogs. Am J Vet Res 48 455-457... 

Maruhn D, Strozyk K, Gielow L, Bock KD (1977) Diurnal variations of urinary enzyme excretion. Clin Chim Acta 75 427-433... 

Figure 29.7. Urinary excretion of proximal tubular enzymes following para-aminophenol (PAP) administration to female Sprague-Dawley rats. Rats received PAP (300mg/kgip) and urine was collected for 24 hr following treatment. Urine was assayed for activities of y-glutamyl transpeptidase (GGTP, O), trehalase (TRE, ), and A-acetyl-P-glucosaminidase (NAG, ). Data are expressed as a percentage of enzyme excretion in rats treated with saline. Each data point represents the mean standard error of at least four determinations. GGTP and TRE are enzymes located primarily on the brush border of proximal tubule cells, and NAG is an intracellular enzyme.

Braunlich H, Fleck C. 1981. Urinary enzyme excretion as a indicator of nephrotoxicity in dependence on age. Exp Pathol 20(3) 182-7. 

Evidence for renal oxalate toxicity was found from studies describing urinary enzyme excretion suggesting renal (tubular) damage in patients with stones [25]. Rat models of stone disease have been used to study such damage in greater detail and revealed brush border loss, release of cellular enzymes, and epithelial erosion [19, 26, 27]. However, all these arguments are indirect and cannot distinguish oxalate (or oxalic acid) mediated effects from calcium oxalate crystal induced effects. 

Meyer BR, Fischbein A, Rosenman K, Lerman Y, Drayer DE, Reidenberg MM. Increased urinary enzyme excretion in workers exposed to nephrotoxic chemicals. Am J Med 1984 76 989-998. 

Figure 3. Activity of porphyrin synthesis enzymes. , excretion , non-excretion condition. Activity is expressed as nmol/mg protein/ min at 40°C.

Acute renal toxicity may occur within days of initiating therapy. Serum creatinine concentration rises and creatinine clearance decreases. Hypertension, hyperkalemia, sodium avidity, and hypomagnesemia may occur. No urine sediment abnormalities are seen. Urinary enzyme excretions increase, but are not reliable indicators of toxicity. Renal biopsy reveals thickening of arterioles, mild focal glomerular sclerosis, proximal tubular epithelial cell vacuolization and atrophy, and interstitial fibrosis. Biopsy is useful to distinguish acute cyclosporine nephrotoxicity from renal allograft rejection, the latter being evidenced by cellular infiltration. ... 

D Amico G, Bazzi C. Urinary protein and enzyme excretion as markers of tubular damage. Curr Opin Nephrol Hypertens 2003 12 639-643. 

R Kondo, K Kurashiki, K Sakai. In vitro bleaching of hardwood kraft pulp by extracellular enzymes excreted from white rot fungi in a cultivation system using a membrane filter. Appl Environ Microbiol 60 921-926, 1994. 

Most authors define CMIN by an increase of serum creatinine of more than 1 mg/ dl 2-3 days after CM exposure. Other reasons for an acute deterioration of renal function have to be excluded. Some investigators even believe that a lower increase of serum creatinine (0.5 mg/ dl 2-4 days after CM) also should be classified as CMIN. It would also be prudent to look for a fall of GFR (general >25% from basehne) with more sensitive methods (i.e. inuhn clearance, iothahnate clearance, iohexol clearance [7. Next to changes in GFR or serum creatinine levels an increase in urinary enzyme excretion seems to also be a sensitive marker of tubular damage after CM exposure [7, 8]. However, no conclusive relationship has been demonstrated between the detection of enzymes in urine and the fall in GFR [8-11]. 

Morphological changes have been observed mainly as vacuolar changes in the proximal convoluted tubular cells [6,12,13]. These morphological changes parallel the increases in urinary enzyme excretion [6,14], but a strong relationship to renal function impairment after CM has not been demonstrated [15]. 

Whiting PFI, Thomson AW, Simpson J6. Cyclosporine and renal enzyme excretion. Clin Nephrol 1986 25 (suppi 1) SI 00-SI 04. 

In the stationary phase of the batch fermentation, enzyme activity begins to decrease due to an increasingly unfavorable environment. In the membrane fermentor, protease (the enzyme) continued to be excreted by the growing biomass for 50 hours. The ratio of enzyme excreted per unit mass of cell produced in the membrane system (70 units/mg) was almost twice that from the batch system (45 units/mg). This would indicate that under the more favorable environment in the membrane fermentor, the organism is more efficient. 

Nephrotoxicity of dmgs, evalnated by renal enzyme excretion studies. Archives... 

Thrombin and factor Xa are prominent players in the blood clotting cascade. They are, therefore, important targets for the development of new anticoagulant/antithrombotic drugs. Trypsin is an enzyme excreted by the pancreas for helping in digestion, and has classically been used as a model enzyme for the whole serine protease family. Thus, in order to minimize side-effects of thrombin/factorXa inhibitors, and to enhance their bioavailability, potential drugs should exhibit selectivity towards thrombin/factorXa with respect to trypsin. 

Fig. 1 Degradation of insoluble substrate by extracellular enzyme excreted from fungal hyphae and utilization of soluble materials for the growth of fungus...

The balance between PrA occurring in the fermenting wort as a result of cell autolysis and/or enzyme excretion of whole cells is still an issue to be examined. Nevertheless, the occurrence of active PrA is important because of its negative effect on beer foam stability. 

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