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At least 19 recordsLinked to original sources
PubMed1975

Hybrid alpha-amylases produced by the transformants of Bacillus subtilis. III. A possible mechanism of formation of hybird alpha-amylases.

Alpha-Amylases (NA64 and NA20) produced by the representative transformants Bacillus subtilis NA64 and NA20 were hybrid enzymes between the two parental alpha-amylases (NAT and MAR) produced by the DNA donor strain of Bacillus natto IAM 1212 and the DNA recipient strain of B. subtilis 6160, a derivative of B. subtilis 168. In order to elucidate a possible mechanism of formation of the hybrid alpha-amylases, 14C-labeled alpha-amylase (SAC) produced by B. subtilis var. amylosarcchariticus, [3H]lysine- and [3H]arginine-labeled alpha-amylases (MAR, NA64, NA20, NAT and SAC), [3H]lysine-labeled alpha-amylase (SAC) and [3H]glucosamine-labeled alpha-amylase (NA64) were purified through ammonium sulfate precipitation, carboxy-methylcellulose and DEAE-Sephadex A-50 column chromatography and immunoprecipitation with rabbit antiserum against alpha-amylase (SAC). Peptide compositions of the tryptic digests from the labeled alpha-amylases were analyzed by double-label AG 50W-X2 column chromatography. On the other hand, amino- and carboxy-terminal amino acid residues of unlabeled alpha-amylases (MAR, NA64, NA20 and NAT) were analyzed. Based on these results, the possibility of DNA recombination events in the alpha-amylase structure gene and on the previous results, we attempted to estimate possible peptide arrangements for the four alpha-amylases (MAR, NA64, NA20 and NAT) and possible recombination regions to form the hybrid enzymes introduced by the DNA-mediated transformation of B. subtilis 6160.

Amino Acids↗
PubMed1979

Radioimmunoassay for human pancreatic amylase: comparison of human serum amylase by measurement of enzymatic activity and by radioimmunoassay.

A radioimmunoassay (RIA) for human pancreatic amylase has been developed for the determination of human serum amylase content. The assay was shown to be sensitive (7 ng/ml), reproducible and specific, but human pancreatic amylase and salivary amylase could not be distinguished by the antiserum used. In normal subjects, the mean concentration of amylase determined by the RIA was found to be 122.1 ng/ml (range: 55--250 ng/ml). A good correlation was observed between the concentration of amylase and its enzymatic activity in normal subjects. In some instances with high amylase activity, however, the rise in enzymatic activity was not accompanied by increasing amount of amylase content.

Amylases↗
PubMed1977

On the quantitation of Iso-amylases in serum and the diagnostic value of serum pancreatic type amylase in chronic pancreatitis.

The object of this study is to elucidate whether the quantitative determination of serum pancreatic type iso-amylase can be used as a diagnostic test for exocrine pancreatic insufficiency. We describe the normal appearance of serum amylase zymograms produced with an agarose electrophoresis technique and the reference values from studies of 142 normal subjects for salivary and pancreatic type amylases. The patient group comprises 95 cases assumed to be representative of a patient population in which verification or exclusion of a diagnosis of chronic pancreatitis is of importance. In this group exocrine pancreatic function has been assessed by means of the Lundh meal test. We find that a low serum pancreatic type amylase value indicates the presence of a reduced exocrine pancreatic function (p = 0.96), and that a normal or elevated serum pancreatic type amylase value excludes the presence of a severe exocrine pancreatic insufficiency (p = 0.91). We also describe the occurrence of an abnormal amylase fraction which may be of diagnostic significance in pancreatic disease.

Adult↗
PubMed1977

Influence of amylase assay technique on renal clearance of amylase-creatinine ratio.

The influence of amylase assay technique on the renal amylase/creatinine clearance measurement was determined by analysis of serum and urine specimens obtained from 10 normal subjects. CAm/CCr averaged 2.19 +/- 0.18% with a saccharogenic technique, 1.52 +/- 0.2% with an iodometric technique, and 0.80 +/- 0.08% with a chromogenic technique. Each of these values differed significantly (P less than 0.05) from the other two. Recovery studies were carried out by adding partially purified human salivary or pancreatic amylase to human newborn serum or urine (which contain minimal endogenous amylase). Equal amylase activity was recovered from serum and urine by the saccharogenic technique whereas recovery from urine was less than 50% of that from serum using the iodometric and chromogenic techniques. The accuracy of the chromogenic technique is markedly improved by the addition of albumin to the urine assay system. Although it appears that only the saccharogenic method provides an accurate estimate of CAm/CCr, each assay technique distinguished the elevated CAm/CCr of patients with pancreatitis from the normal range established for that technique. Accurate clinical interpretation of CAm/CCr measurment requires knowledge of the amylase assay technique used.

Amylases↗
PubMed1978

Hydrolysis of aryl beta-maltotriosides by sweet potato beta-amylase and soybean beta-amylase.

Sweet potato beta-amylase [EC 3.2.1.2, alpha 1,4-D-glucan maltohydrolase]-catalyzed hydrolyses of aryl beta-maltotriosides with substituents, NO2-, Cl-, and Br- at the o-, m-, and p-positions in the phenyl ring were studied at pH 4.8 and 25 degrees C. The hydrolyses of a few of the maltotriosides by soybean beta-amylase [EC 3.2.1.2, alpha-1,4-D-glucan maltohydrolase] were also studied at pH 5.4 and 25 degrees C. It was found that the aryl beta-maltotriosides were preferentially hydrolyzed into maltose and aryl beta-D-glucosides by both beta-amylases. The Michaelis constant Km and the molecular activity ko were determined for the hydrolyses of these maltotriosides and compared with those of maltotriose and maltotetraose. Aryl beta-maltotriosides were more rapidly hydrolyzed than maltotriose by a factor of 30--80, and more slowly hydrolyzed than maltotetraose by a factor of 10--30, depending on the kinds of substituents. The rapid hydrolysis of aryl beta-maltotrioside as compared with maltotriose may be due to the interaction of an aryl group with the subsite of beta-amylase. This is in contrast with glucoamylase [EC 3.2.1.3, alpha-1,4-D-glucan glucohydrolase] of Rhizopus niveus-catalyzed hydrolysis of phenyl beta-maltoside, whose phenyl group does not interact so much with the subsite of the enzyme.

Amylases↗
PubMed1979

Amylase-producing ovarian neoplasm with pseudo-Meigs' syndrome and elevated pleural fluid amylase: case report and ultrastructure.

Elevated amylase activity was noted in the pleural effusion of a patient who was later found to have a stage I low-grade serous papillary ovarian neoplasm. The effusion resolved spontaneously after resection of the ovarian tumor, which contained large amounts of amylase activity. The ultrastructure of the tumor epithelium resembled that of normal salpinx. Secretory-type cells were present with apical, variably electron-dense secretory granules and cytoplasmic glycogen deposits. Amylase activity in the ovarian neoplasm probably resulted from the presence of functioning endosalpingeal-type epithelium in the tumor. In cases of effusion with unexplained amylase elevations, the possibility of serous ovarian neoplasia should be considered, even in the absence of demonstrable extra-ovarian dissemination.

Amylases↗
PubMed1979

The amylase-producing microflora of semi-preserved canned sausages: identification of the bacteria and characterization of their amylases.

Thirteen strains of amylase-producing bacteria were isolated from semi-preserved canned sausages and their ingredients. All belonged to the genus Bacillus, and could be separated into 4 different groups. Two groups were different strain of B. subtilis, one was B. amyloliquefaciens and the last was B. macerans. The identification of the different bacteria species was supported by disc gel electrophoresis of the supernatant culture fluid, after growth. The amylases were characterized with regard to temperature optimum, pH optimum and thermostability. Although some of the amylases appear to be quite thermostable, the only explanation for starch degradation in semi-preserved foods seems to be the amylase production from outgrowing spores which survived the heat treatment.

Amylases↗
PubMed1976

Serum amylase activity and renal amylase activity clearance in patients with severely impaired renal function and in patients treated with renal allotransplantation.

Serum amylase activity was measured in 29 nondialysed patients with severe renal failure, in 24 uraemic patients treated with chronic haemodialysis, and in 29 patients treated with renal allotransplantation. Simultaneous measurement of renal amylase activity clearance (CAm) and creatinine clearance (CCr) was performed in 25 patients with severe renal failure and in 19 transplanted patients. Serum amylase activity was elevated in all three groups. CAm was significantly correlated to CCr both in the group with severe renal failure and in the transplanted group. Unlike in the group of transplanted patients, the ratio CAm/CCr was significantly increased in patients with severe impaired renal function. It is concluded that the elevation of serum amylase activity in patients with impaired renal function is primarily due to decreased glomerular filtration rate. The value of CAm/CCr for diagnosing acute pancreatitis is doubtful in patients with severe renal disease.

Amylases↗
PubMed1979

Amylase-creatinine clearance ratios and serum amylase isoenzymes in moderate renal insufficiency.

Both the amylase-creatinine clearance ratio (normal 1.55%) and proportion of pancreatic isoamylase in serum (normal 41.0%) increase in acute pancreatitis, and are therefore useful measurements to support that diagnosis. Whether renal insufficiency interferes with the accuracy and specificity of these tests has been debated. Our study indicates that even moderate renal insufficiency (creatinine clearance 30.5 ml/minute) raises the amylase-creatinine clearance ratio (3.23%) close enough to values characteristic of acute pancreatitis (4.41%) to cause potential diagnostic confusion. The fraction of pancreatic isoamylase in serum is also increased (69.9%), but not to the levels of acute pancreatitis (91.0%). We therefore caution against the use of the amylase-creatinine clearance ratio for the diagnosis of acute pancreatitis in patients with moderate renal insufficiency.

Acute Disease↗
PubMed1977

The frequency of marcroamylasemia and the diagnostic value of the amylase to creatinine clearance ratio in patients with elevated serum amylase activity.

190 patients with elevated serum amylase levels were tested for macroamylasemia and the amylase to creatinine clearance ratio. Macroamylasemia was found in 3 patients. In these patients macroamylasemia persisted after the total activity of serum amylase had fallen to nearly normal levels. The Cam/Ccr-ratios were determined 14 times in the 3 macroamylasemic patients. Only one of the 14 values was clearly less than 1%. Cam/Ccr-ratios above 4% were found in 83 patients. In 56 of them the diagnosis of acute pancreatitis could not be confirmed. 19 out of 46 patients with the established diagnosis of acute pancreatitis had Cam/Ccr-ratios below 4%. Cam/Ccr-ratios below 1% were also found in patients without macroamylasemia. It is concluded that high and low Cam/Ccr-ratios are not specific for acute pancreatitis and macroamylasemia, respectively, and--moreover--that a normal Cam/Ccr-ratio excludes neither acute pancreatitis nor macroamylesemia.

Acute Disease↗
PubMed1975

Determination of amylase activity and amylase isoenzymes in serum and urine using a solid phase blue starch substrate.

The alpha-amylase of serum and urine was determined in 40 healthy people using the modified "Phadebas Amylase Test". The original method was modified by decreasing the incubation volume to one millilitre and by adding to all urine speciemens a small amount of albumin in saline. The normal values obtained are slightly higher than those obtained by the original method. The amylase isoenzymes were likewise determined from the serum and urine of the same 40 healthy people. For separation were used electrophoresis on cellulose acetate and Phadebas tablets as substrate. These urine and serum isoamylases were investigated and compared. The distributions obtained deviate somewhat from ones reported earlier. The clinical usefulness of isoamylase is briefly discussed.

Acute Disease↗
PubMed1976

Serum amylase determinations and amylase to creatinine clearance ratios in patients with chronic renal insufficiency.

Patients with severe chronic renal failure may have significant hyperamylasemia in the absence of clinical symptoms or signs of acute pancreatitis. Amylase to creatinine clearance (CA/CC) ratios were usually elevated in patients with chronic renal failure and were not helpful in evaluating the possibility of acute pancreatitis. The mean amylase to creatinine clearance ratio for the controls with normal renal function was 1.24 +/- 0.13. In patients with chronic renal failure, it was 3.17 +/- 0.42 (P less than 0.001). Serum amylase isoenzyme patterns revealed no difference in salivary to pancreatic isoenzyme ratios between normals (1.04 +/- 0.12) and patients with severe renal insufficiency without evidence of pancreatic disease (1.07 +/- 0.13). The isoenzymes were helpful in excluding the diagnosis of pancreatic in 1 renal failure patient whose hyperamylasemia was primarily salivary in origin and in confirming the diagnosis in another who had only a pancreatic band.

Adult↗
PubMed1978

Studies on the substrate specificity of Taka-amylase A1. XIV. Preparation of 6-deoxy-6-halogenomaltotrioses and their hydrolysis by Taka-amylase A.

1. O-6-Deoxy-alpha-D-glucopyranosyl-(1 leads to 4)-O-alpha-D-glucopyranosyl-(1 leads to 4)-D-glucopyranose, O-6-chloro-6-deoxy-alpha-D-glucopyranosyl-(1 leads to 4)-O-alpha-D-glucopyranosyl-(1 leads to 4)-D-glucopyranose, O-6-bromo-6-deoxy-alpha-D-glucopyranosyl-(1 leads to 4)-O-alpha-D-glucopyranosyl-(1 leads to 4)-D-glucopyranose, and O-6-deoxy-6-iodo-alpha-D-glucopyranosyl-(1 leads to 4)-O-alpha-D-glucopyranosyl-(1 leads to 4)-D-glucopyranose were prepared, taking advantage of the substrate specificities of Taka-amylase A and glucoamylase, and the action of Taka-amylase A on these substrates was investigated. 2. The Michaelis constant Km and the molecular activity ko were determined at 37 degrees C and pH 5.2 using the modified maltotrioses. The values of Km and ko decreased upon modification of maltotriose and those of ko/Km were in agreement with the comparative initial rates for the corresponding derivatives of phenyl alpha-maltoside at low substrate concentrations. This result suggested that a subsite of the enzyme may have a specific interaction with halogen atoms in the substrate. 3. All halogenomaltotrioses examined showed substrate inhibition at high substrate concentrations.

Amylases↗
PubMed1979

Specificity of serum amylase and amylase creatinine clearance ratio in the diagnosis of acute and chronic pancreatitis.

In 31 patients with pancreatitis, the amylase to creatinine clearance ratio (CACR) was significantly greater than for controls (10.7 +/- 1.7 vs. 2.6 +/- 0.3, P less than .001). Sixteen pancreatitis patients with serum amylase (SAm) within the normal range had a mean CACR significantly greater than that of 19 hospital control patients with normal SAm (9.2 +/- 1.5 vs. 3.0 +/- 0.4, P less than .001). For control patients a highly significant inverse correlation between SAm and CACR was observed. No relationship was detected between these parameters for pancreatitis patients. The results suggest that the CACR may be of aid in establishing the diagnosis of pancreatitis even in patients without hyperamylasemia.

Acute Disease↗
PubMed1979

[Lung cancer with elevated amylase activity. One observation with study of amylase's isoenzymes (author's transl)].

Amylase is composed by two isoenzymes groups: pancreatic or salivary type. This last part can be increased in many diseases. A case of lung cancer with elevated amylase activity in blood, urine and pleural fluid is reported in a 74-year-old man. This increase was due to salivary type isoamylases with an unusual component which disappeared by neuraminidase treatment. The significance and the origin of this hyperamylasemia with non pancreatic cancer are discussed.

Adenocarcinoma↗
PubMed1977

Biosynthesis of alpha-amylase and protease by Streptomyces olivaceus 142. I. Regulation of alpha-amylase activity.

Streptomyces olivaceus 142 produces amylase in the logarithmic phase of growth of the culture. The synthesis of the enzyme is induced by maltose and starch. In the case of maltose the synthesis is induced by a contaminating compound, probably being a higher than maltose polymer of glucose. The synthesis of amylase is negatively controlled by catabolic repression. The level of the activity of the enzyme depends not only on the biosynthesis but also on it proteolytic degradation.

Amylases↗