Optimization of fibrinase productivity from Actinomycetes

Fibrinolytic enzymes that dissolve blood clots and show promise for thrombosis therapy have been successfully identified from various sources. A wide range of microorganisms has been screened for their fibrinolytic properties. A fibrinolytic protease has been isolated from Streptomyces violaceoruber and Streptomyces spiroverticillatus culture filtrate. The purification procedure involved ammonium sulphate fractionation, dialysis, calcium phosphate gel purification and gel filtration on Sephadex G-100. By using native polyacrylamide gel electrophoresis [Native PAGE] to determine molecular weight of the enzyme. The optimum temperature for the high production of fibrinase from S. violaceoruber was 30[degree] C and from S. spiroverticillatus was 35[degree] C and the optimum pH was 9.0. The best incubation period is 6 days. The incorporation of lactose as carbon source, yeast extract as nitrogen source and MnCl[2] to culture media highly increased the production of fibrinase from the two species. The molecular weight was about 30 KDa. It exhibited fibrinolytic enzyme activity. In vitro studies revealed that fibrinase dissolves clots made by blood

Prognosis of Korean patients with primary biliary cirrhosis / 대한간학회지

No abstract available.

Clinical features and prognosis of primary biliary cirrhosis in Korea / 대한간학회지

BACKGROUND/AIMS: This study investigated the clinical features and prognosis of primary biliary cirrhosis (PBC) in Korea. METHODS: Clinical data of patients diagnosed as PBC between 1997 and 2008 at eight referral hospitals were analyzed retrospectively. PBC was diagnosed based on liver function tests, presence of serum antimitochondrial antibody (AMA), and histopathological findings. RESULTS: In total, 251 patients (218 females, 33 males; mean age 54 years) were enrolled, and the mean follow-up duration was 33.5 months. At the diagnosis, 61% of the patients were asymptomatic, 12% had decompensated liver cirrhosis, and 98% were positive for AMA. The serum alkaline phosphate (ALP) level was 2.6 times the upper limit of normal, aspartate aminotransferase was 105 U/L, and bilirubin was 2.0 mg/dL. The mean Mayo risk score was 5.5, and the Child-Pugh class was A, B, and C in 79%, 19%, and 2% of the patients, respectively. Ursodeoxycholic acid (UDCA) was used for treatment in 88% of the patients, among which 70% exhibited biochemical responses defined as normalization or a >40% decrease in ALP at 6 months. Eight deaths occurred during the follow-up; the causes were variceal bleeding, hepatic failure, and sepsis. The overall 5-year survival rate was 95%. The poor prognostic factors were being older than 60 years, high bilirubin, low albumin, ascites, high Mayo risk score, Child-Pugh class C, and initial presence of hepatic decompensation. CONCLUSIONS: Most patients diagnosed as PBC were asymptomatic, and these patients had a favorable short-term prognosis. The prognosis of PBC was dependent on the initial severity of liver disease.

Studies on proteases and alpha-macroglobulin activity in amphibian blood plasma.

Frog plasma effectively hydrolysed the synthetic chromogenic substrates, H-D-Glu-Gly-Arg-p-nitroanilide (S-2444), benzoyl-Ile-Glu-Gly-Arg-p-nitroanilide (S-2222) and acetyl-Ile-Glu-Gly-Arg- p-nitroanilide (S-2423), all sensitive substrates for trypsin. Moderate hydrolytic activities was observed with H-D-Phe-Pip-Arg-p-nitroanilide (S-2238, substrate for thrombin) and H-D-Pro-Phe-Arg-p-nitroanilide (S-2302, substrate for plasma kallikrein). Frog plasma contained moderate alpha-macroglobulin activity. When plasma was incubated at 37 degrees C, the macroglobulin activity decreased in a time dependent manner while only a moderate decrease in the protease activity was observed. Ten fold dilution of plasma with 0.1 M phosphate buffer, pH 7.6 prevented the inherent loss of macroglobulin activity but it had no effect on protease activity. Dye ligand chromatography of the plasma on red Sepharose revealed that bulk of alpha-macroglobulin activity along with minor proteolytic activity (S-2222 hydrolysis) was present i the washings. On the other hand, about one third of the alpha-macroglobulin activity and bulk of the protease activity was bound to the column and were eluted with 1.5 M NaCl. alpha-Macroglobulin activity in red Sepharose washings and elutions on chromatography on Sephadex G-200, was eluted in two regions with Ve/Vo value of 1.33 and 1.08, respectively.

Ubiquitin with a non-ATP-dependent slow intrinsic proteolytic activity: a mild and rapid purification procedure.

Ubiquitin has been purified to homogeneity, through a dialysis membrane having a NMW cutoff of 12 kDa, by taking advantage of its non-dialysable nature under these conditions. The dialysate was continuously recycled through a CM-52 cation exchange column at pH 4.5. The adsorbed fraction was eluted selectively at pH 7.2. Ubiquitin (25 mg) was obtained from 500 ml of packed RBCs. On SDS PAGE, ubiquitin showed varying mobility depending on the time of boiling in SDS. With 2 min of boiling, the molecular weight seemed to be 10.5 kDa, whereas 10 min of boiling resulted in a molecular weight of 8.5 kDa. Ubiquitin showed a slow intrinsic proteolytic activity against SDS-denatured beta-galactosidase in the absence of ATP. For the first 4 hr, there was no detectable degradation, but degradation was nearly complete after 8 hr. These data are not in agreement with those of Freid et al. [Proc. Natl Acad. Sci, USA, 84 (1987), 3685] who have reported a proteolytic activity comparable to that of other proteolytic enzymes.

Further studies on proteinases and alpha 2-macroglobulin activity in diabetic plasma.

Loss of chymotrypsin binding capacity of alpha 2-macroglobulin in diabetic plasma on in vitro incubation, could be partially prevented by phenylmethyl sulphonyl fluoride and pepstatin A. Prior ten-fold dilution of plasma with 0.02 M phosphate buffer (pH 7.0) completely arrested the process. The phenomenon could not be reactivated by Ca2+, lecithin or bovine serum albumin. Diabetic plasma, like normal plasma, exhibited maximal hydrolytic activities on H-D-Pro-Phe-Arg-p-nitroanilide, H-D-Val-Leu-Arg-p-nitroanilide and H-D-Ile-Pro-Arg-p-nitroanilide. The hydrolytic activities were not significantly diminished on incubation of plasma at 37 degrees C for 12 hr, unlike alpha 2-macroglobulin activity. On gel chromatography on Sephadex G-200, part of the proteolytic activity in diabetic plasma coeluted with alpha 2-macroglobulin in the VO region. A second activity peak (absent in normal plasma) was eluted with a Ve/V0 value of 1.40. Possible role of free proteinases in diabetic plasma in the inactivation of alpha 2-macroglobulin is discussed.