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PubMed1992

The admission serum lipase:amylase ratio differentiates alcoholic from nonalcoholic acute pancreatitis.

To determine whether the lipase:amylase ratio differentiates alcoholic from nonalcoholic pancreatitis, we conducted a retrospective review of charts with the diagnosis of acute pancreatitis at the George Washington University Medical Center between January 1988 and July 1990. A total of 446 charts were reviewed. For a patient to be included in the subsequent analysis, the following criteria were met: 1) the patient had typical symptoms of pancreatitis, 2) serum amylase and lipase were analyzed on admission, and 3) a computerized tomographic (CT) scan or ultrasound of the abdomen was obtained within 72 h of admission. Forty-seven charts satisfied the requirements for inclusion in the study. Data collected from the charts included history of alcohol consumption, age, sex, race, admission serum amylase and serum lipase (from this the amylase:lipase ratio was calculated), peak serum amylase and serum lipase, and number of days of abdominal pain before admission. Patients with alcoholic pancreatitis had significantly lower serum amylase levels and significantly higher lipase:amylase ratios than those with nonalcoholic pancreatitis (p < 0.01). There was no difference in the serum lipase between the groups. The higher the lipase:amylase ratio, the greater the specificity of alcohol as the etiology of acute pancreatitis. Only patients with alcoholic acute pancreatitis had lipase:amylase ratios > 5.0 (sensitivity 31%, specificity 100%). Our data point to the clinical utility of the lipase:amylase ratio in differentiating alcoholic from nonalcoholic acute pancreatitis. Prospective studies will be needed to confirm the clinical utility of this ratio.

Acute Disease↗
PubMed1992

Serum amylase activity and calcium and magnesium concentrations in young cattle grazing fescue and Bermuda grass pastures.

The study reported here was part of a long-term investigation of the effects of genotype on growth, reproduction, and metabolism in cattle grazing common Bermuda grass and endophyte-infected fescue pastures. In June 1990, blood samples were collected from the tail vein of yearling heifers and steers (Angus [AA], Brahman [BB], and their reciprocal crosses [AB, BA], n = 97). Serum amylase activity was assayed enzymatically; serum Ca and Mg concentrations were determined by atomic absorption spectrophotometry. The effects of endophyte-infected fescue depended on genotype (P less than 0.001). In yearlings having at least 1 Angus parent (AA, AB, BA), grazing endophyte-infected fescue was associated with higher serum amylase activity than was grazing Bermuda grass. But serum amylase activities of BB yearlings consuming either forage were similar. Moreover, for either forage, substantial differences were related to genotype (P less than 0.007) and gender (P less than 0.05). Angus yearlings had higher serum amylase activity than did Brahman yearlings; AB and BA yearlings had intermediate values. Heifers had higher amylase activity than did steers. The relationship among serum values of amylase, Ca, and Mg depended on forage. Yearlings consuming endophyte-infected fescue and having at least 1 Angus parent had a moderate negative correlation between serum amylase activity and Ca concentration (r = -0.53; P less than 0.0005); that is, in calves of genotypes with increased amylase activity while consuming endophyte-infected fescue (AA, AB, BA), the higher the amylase activity, the lower the serum Ca concentration. However, in yearlings consuming Bermuda grass, serum amylase and Ca values were not correlated.(ABSTRACT TRUNCATED AT 250 WORDS)

Amylases↗
PubMed1960

Serum amylase in peptic gastroduodenal perforation. A study to determine the significance of abnormally high levels.

Elevated serum amylase is a frequent concomitant of perforated gastroduodenal ulcer. To determine if there might be significant correlation between an increase in amylase and some of the other factors associated with ulcer perforation, a study was made of the clinical records of 1,000 patients with perforation of gastroduodenal ulcers. Sixteen per cent of the patients had amylase levels of 200 Somogyi units or more. This rise in serum amylase comes about in cases of perforated peptic ulcer as a result of peritoneal lymphatic absorption of fluid containing pancreatic enzyme which is spilled through the perforation. Among patients with perforated ulcers and elevated serum amylase levels, the higher the amylase level, the higher the mortality rate. The factors of amount of abdominal fluid spill, the duration of the perforation before surgical closure, the size of the perforation, shock and recent ingestion of food were also studied for possible relationship with elevated serum amylase. All appeared to be statistical if not etiological associates of abnormal serum amylase levels. Because high amylase values so often occur in perforated ulcer, there is no amylase level that can be considered diagnostic of acute pancreatitis.

Amylases↗
PubMed1991

Metabolic derepression of alpha-amylase gene expression in suspension-cultured cells of rice.

We present evidence to show that the alpha-amylase gene family in rice is under two different modes of regulation: 1) hormonal regulation in germinating seeds, and 2) metabolic repression in cultured cells by available carbohydrate nutrients. Expression of alpha-amylase genes in deembryoed rice seeds is known to be induced by exogenous gibberellic acid. On the other hand, expression of alpha-amylase genes in suspension-cultured cells is induced by the deprivation of carbohydrate nutrient. A lag period of 2-4 h is required for the induction of alpha-amylase mRNA in sucrose-depleted medium. The induction of alpha-amylase expression is extraordinarily high and levels of alpha-amylase mRNA can be increased 8-20-folds after 24 h of sucrose starvation. The synthesis and secretion of alpha-amylase is also dependent upon the level of carbon source. The derepression or repression of alpha-amylase synthesis can be readily reversed by the deprivation or replenishment of sucrose in the medium, respectively. Glucose and fructose exert a repression on the alpha-amylase synthesis similar to that of sucrose. A hypothesis that explains the induction of alpha-amylase synthesis by carbohydrate starvation is proposed. Our data have suggested a hitherto undiscovered, potentially important control mechanism of carbohydrate metabolism in higher plants.

Blotting, Northern↗
PubMed1986

Catalytic concentrations of amylase isoenzymes: an assay with wheat-germ inhibitor and 4-nitrophenylmaltopentaoside plus 4-nitrophenylmaltohexaoside as substrate.

We coupled a kinetic procedure to a selective inhibiting method for determining amylase isoenzymes in biological samples, using 4-nitrophenylmaltopentaoside plus 4-nitrophenylmaltohexaoside as substrate and a wheat-germ selective inhibitor with the Gilford S-III spectrophotometer. On plotting remaining amylase activities/total amylase activities (R/T) vs pancreatic amylase activities/salivary amylase activities (P/S) ratios, we found the curve to be linear for P/S ratios from 0.2 to 5. The inhibition rate of amylase inhibitor was constant in solutions having total amylase activities between 20 and (at least) 900 U/L. CVs were 3.1 to 7.1% for pancreatic amylase and 2.0 to 12.9% for salivary amylase in serum. Correlation with the Phadebas method was excellent (r = 0.99) for both pancreatic and salivary amylase. We also automated this procedure in an Hitachi 705 analyzer and correlated the results (r = 0.99) with those by our manual method.

Amylases↗
PubMed1984

Amylase isoenzymes in the evaluation of trauma patients.

In traumatized patients, elevation of the levels of serum amylase is often noted and may lead to a diagnosis of pancreatitis or pancreatic injury. In the presence of multiple injuries, it is often difficult to evaluate clinically for pancreatitis or pancreatic injury. Since the serum amylase is derived from both the pancreatic and the salivary glands, it is useful to determine the origin of the elevated levels of serum amylase in these patients. A total of 31 patients including 21 trauma patients were studied, and the total serum amylase and also the pancreatic (P) and salivary (S) fractions were determined by isoelectric focusing. Compared with the normal control group, most trauma victims had elevated total amylase levels (normal, 30-128 U). In six patients with head and facial trauma, the P-fraction was 7.6 per cent, and the S-fraction was 92.4 per cent (normal, P 35-50%; S 50-65%), while in six patients with penetrating abdominal trauma, the P-fraction was 81 per cent, and the S-fraction was 19 per cent. These differences were statistically significant. The data demonstrate the value of measuring fractions of amylase in addition to total amylase levels. In patients with head and facial trauma alone, elevated levels of serum amylase are due to an increase in the salivary fraction. Elevation of total serum amylase in traumatized patients does not necessarily indicate pancreatic injury. Measurements of amylase fractions were thus useful in evaluation of trauma patients.

Amylases↗
PubMed1978

Sensitivity of the amylase-creatinine clearance ratio in acute pancreatitis.

An elevated amylase-creatinine clearance ratio has been established as being highly specific for the diagnosis of acute pancreatitis. In the present study, the sensitivity of this test was compared to that of the serum amylase and the one-hour urinary amylase test in 29 patients with acute pancreatitis. Abnormal elevations of the amylase-creatinine clearance ratio were found less frequently than abnormal elevations of the serum and one-hour urinary amylases. Moreover, abnormal elevations of the amylase-creatinine clearance ratio showed less deviation from normal and values returned to normal sooner than those of the serum and one-hour urinary amylases. When compared to the serum amylase and the one-hour urinary amylase tests, the amylase-creatinine clearance ratio is a relatively insensitive test in patients with acute pancreatitis.

Acute Disease↗
PubMed1993

An immunohistochemical survey of amylase isoenzymes in cholangiocarcinoma and hepatocellular carcinoma.

It is well known that neoplastic cells of several organs produce amylases. However, to our knowledge, alpha-amylase expression has not been reported in hepatic neoplasms. In the present study, we surveyed the expression of alpha-amylase isoenzymes in cholangiocarcinoma (CCC) (n = 18) and hepatocellular carcinoma (n = 20) by an immunohistochemical technique, using four polyclonal and monoclonal antibodies against salivary- and pancreatic-type amylases. In CCC, salivary- and pancreatic-type amylase immunoreactivity was found in the tumor cell cytoplasm in 11 (61%) and eight (44%) cases, respectively. There was a tendency for salivary- and pancreatic-type amylases to appear in the same CCC. The proportion of isoamylase-positive cases was high in well-differentiated CCC (75%), intermediate in moderately differentiated CCC (66%), and low in poorly differentiated CCC (25%). In contrast, hepatocellular carcinoma cells were negative for salivary- and pancreatic-type amylases. Intrahepatic large bile ducts of nontumorous areas frequently expressed both amylase isoenzymes, while nonneoplastic hepatocytes were negative for both isoamylases. These results suggest that biliary epithelial cells retain amylase isoenzymes after malignant transformation. The finding that the expression of amylase isoenzymes was correlated with the histologic differentiation in CCC supports this suggestion.

Adenoma, Bile Duct↗
PubMed2000

Advances in microbial amylases.

This review makes a comprehensive survey of microbial amylases, i.e. alpha-amylase, beta-amylase and glucoamylase. Amylases are among the most important enzymes and are of great significance in present-day biotechnology. Although they can be derived from several sources, such as plants, animals and micro-organisms, the enzymes from microbial sources generally meet industrial demands. Microbial amylases could be potentially useful in the pharmaceutical and fine-chemical industries if enzymes with suitable properties could be prepared. With the advent of new frontiers in biotechnology, the spectrum of amylase application has widened in many other fields, such as clinical, medicinal and analytical chemistries, as well as their widespread application in starch saccharification and in the textile, food, brewing and distilling industries. In this review, after a brief description of the sources of amylases, we discuss the molecular biology of amylases, describing structures, cloning, sequences, and protoplast fusion and mutagenesis. This is followed by sections on their production and finally the properties of various amylases.

Amylases↗
PubMed1965

THE CELL-BOUND ALPHA-AMYLASES OF STREPTOCOCCUS BOVIS.

1. The cell-bound alpha-amylase of Streptococcus bovis has been isolated from other carbohydrases in the cell extract by chromatography on DEAE-cellulose. The enzyme has been compared with the extracellular alpha-amylase produced by this organism. 2. The two amylases had similar action patterns on amylose, the main product being maltotriose with smaller amounts of maltose and a little glucose. 3. The cell-bound amylase hydrolysed maltopentaose and maltohexaose at a similar rate to the hydrolysis of amylose. Maltotetraose was hydrolysed six times more slowly, and maltotriose 280 times more slowly, than amylose. 4. Studies with end-labelled maltodextrins revealed that the cell-bound alpha-amylase preferentially hydrolysed the third linkage from the non-reducing end, liberating maltotriose. The linkage at the reducing end of maltotriose was more easily hydrolysed than the other. 5. Egg-white lysozyme and the extracellular enzymes of Streptomyces albus lysed the cell walls of Streptococcus bovis, releasing amylase into the medium. In the presence of 0.6 m-sucrose 10% of the maximal amylase activity was released by lysozyme. Suspension of the spheroplasts in dilute buffer caused the rupture of the cytoplasmic membrane and the liberation of amylase. 6. A sensitive method for determining the ability of amylases to degrade starch granules is described.

Amylases↗
PubMed1982

Enzymic mechanism of starch breakdown in germinating rice seeds : 12. Biosynthesis of alpha-amylase in relation to protein glycosylation.

The biosynthetic mechanism of alpha-amylase synthesis in germinating rice (Oryza sativa L. cv. Kimmazé) seeds has been studied both in vitro and in vivo. Special attention has been focused on the glycosylation of the enzyme molecule. Tunicamycin was found to inhibit glycosylation of alpha-amylase by 98% without significant inhibition of enzyme secretion. The inhibitory effect exerted by the antibiotic on glycosylation did not significantly alter enzyme activity.In an in vitro system using poly-(A) RNA isolated from rice scutellum and the reticulocyte lysate translation system, a precursor form of alpha-amylase (precursor I) is formed. Inhibition of glycosylation by Tunicamycin allowed detection of a nonglycosylated precursor (II) of alpha-amylase. The molecular weight of the nonglycosylated precursor II produced in the presence of Tunicamycin was 2,900 daltons less than that of the mature form of alpha-amylase (44,000) produced in the absence of Tunicamycin, and 1,800 daltons less than the in vitro synthesized molecule.The inhibition of glycosylation by Tunicamycin as well as in vitro translation helped clarify the heterogeneity of alpha-amylase isozymes. Isoelectrofocusing (pH 4-6) of the products, zymograms, and fluorography were employed on the separated isozyme components. The mature and Tunicamycin-treated nonglycosylated forms of alpha-amylase were found to consist of three isozymes. The in vitro translated precursor forms of alpha-amylase consisted of four multiple components. These results indicate that heterogeneity of alpha-amylase isozymes is not due to glycosylation of the enzyme protein but likely to differences in the primary structure of the protein moiety, which altogether support that rice alpha-amylase isozymes are encoded by multiple genes.

Journal Article↗
PubMed1982

Alpha-amylase secretion by single barley aleurone layers.

The secretion of alpha-amylase from single isolated (Hordeum vulgare L. cv Himalaya) aleurone layers was studied in an automated flow-through apparatus. The apparatus, consisting of a modified sample analyzer linked to a chart recorder, automatically samples the flow-through medium at 1 minute intervals and assays for the presence of alpha-amylase. The release of alpha-amylase from aleurone layers begins after 5 to 6 hours of exposure to gibberellic acid and reaches a maximum rate after 10 to 12 hours. The release of alpha-amylase shows a marked dependence on Ca(2+), and in the absence of Ca(2+) it is only 20% of that in the presence of 10 millimolar Ca(2+). Withdrawal of Ca(2+) from the flow-through medium results in the immediate cessation of enzyme release and addition of Ca(2+) causes immediate resumption of the release process. The effect of Ca(2+) is concentration-dependent, being half-maximal at 1 millimolar Ca(2+) and saturated at 10 millimolar Ca(2+). Ruthenium red, which blocks Ca(2+) but not Mg(2+) efflux from barley aleurone layers, renders alpha-amylase release insensitive to Ca(2+) withdrawal. Inhibitors of respiratory metabolism cause a burst of alpha-amylase release which lasts for 0.5 to 5 hours. Following this phase of enhanced alpha-amylase release, the rate of release declines to zero. Pretreatment of aleurone layers with HCl prior to incubation in HCN also causes a burst of alpha-amylase release, indicating that the inhibitor is affecting the secretion of alpha-amylase and not its movement through the cell wall. The rapid inhibition of alpha-amylase release upon incubation of aleurone layers at low temperature (5 degrees C) or in 0.5 molar mannitol also indicates that enzyme release is dependent on a metabolically linked process and is not diffusion-limited. This conclusion is supported by cytochemical observations which show that, although the cell wall matrix of aleurone layers undergoes extensive digestion after gibberellin treatment, the innermost part of the cell wall is not degraded and could influence enzyme release.

Journal Article↗
PubMed1984

Regulation of the synthesis of barley aleurone alpha-amylase by gibberellic Acid and calcium ions.

The effects of gibberellic acid (GA(3)) and calcium ions on the production of alpha-amylase and acid phosphatase by isolated aleurone layers of barley (Hordeum vulgare L. cv Himalaya) were studied. Aleurone layers not previously exposed to GA(3) or Ca(2+) show qualitative and quantitative changes in hydrolase production following incubation in either GA(3) or Ca(2+) or both. Incubation in H(2)O or Ca(2+) results in the production of low levels of alpha-amylase or acid phosphatase. The addition of GA(3) to the incubation medium causes a 10- to 20-fold increase in the amounts of these enzymes released from the tissue, and addition of Ca(2+) at 10 millimolar causes a further 8- to 9-fold increase in alpha-amylase release and a 75% increase in phosphatase release. Production of alpha-amylase isoenzymes is also modified by the levels of GA(3) and Ca(2+) in the incubation medium. alpha-Amylase 2 is produced under all conditions of incubation, while alpha-amylase 1 appears only when layers are incubated in GA(3) or GA(3) plus Ca(2+). The synthesis of alpha-amylases 3 and 4 requires the presence of both GA(3) and Ca(2+) in the incubation medium. Laurell rocket immuno-electrophoresis shows that two distinct groups of alpha-amylase antigens are present in incubation media of aleurone layers incubated with both GA(3) and Ca(2+), while only one group of antigens is found in media of layers incubated in GA(3) alone. Strontium ions can be substituted for Ca(2+) in increasing hydrolase production, although higher concentrations of Sr(2+) are required for maximal response. We conclude that GA(3) is required for the production of alpha-amylase 1 and that both GA(3) and either Ca(2+) or Sr(2+) are required for the production of isoenzymes 3 and 4 of barley aleurone alpha-amylase.

Journal Article↗
PubMed1989

Release and Activity of Bound beta-Amylase in a Germinating Barley Grain.

In resting grains of Triumph barley (Hordeum vulgare L. cv Triumph) about 40% of the beta-amylase could be extracted with a saline solution, the remaining 60% being in a bound form. During seedling growth (20 degrees C), the bound form was released mainly between days 1 and 3. When a preparation containing bound beta-amylase was incubated with an extract made of endosperms separated from germinating grains, release of bound beta-amylase took place and could be studied in vitro. The release was almost completely prevented by leupeptin and antipain, specific inhibitors of a group of SH-proteinases, but it was not inhibited by pepstatin A or EDTA, which inhibit some other barley proteinases. It is thus very likely that in a whole grain, at least the bulk of the bound beta-amylase is released by the proteolytic action of one or several SH-proteinases. When the bound beta-amylase was released by papain, its molecular weight was about 5000 daltons smaller than that of beta-amylase released by dithiothreitol. This indicates that the release is due to removal of a sequence of beta-amylase itself. A similar decrease in size took place during seedling growth. Bound beta-amylase showed some activity against native starch and it hydrolyzed maltotetraose at a rate that was about 70% of the rate the same amount of bound beta-amylase gave after release. Bound beta-amylase is thus not inactive and it is likely that the slower rate of hydrolysis is due to steric hindrances which prevent substrates from reaching the active site.

Journal Article↗
PubMed1990

Chloroplastic regulation of apoplastic alpha-amylase activity in pea seedlings.

Photobleaching of pea (Pisum sativum L.) seedling leaves by treatment with norflurazon (San 9789) and 7 days of continuous white light caused a 76- to 85-fold increase in the activity of the primary alpha-amylase, a largely apoplastic enzyme, over normally greening seedlings. Levels of chlorophyll were near zero and levels of plastid marker enzyme activities were very low in norflurazon-treated seedlings, indicating severe photooxidative damage to plastids. As levels of norflurazon or fluence rates were lowered, decreasing photobleaching of tissues, alpha-amylase activity decreased. Levels of leaf beta-amylase and starch debranching enzyme changed very little in norflurazon-treated seedlings. Infiltration extraction of leaves of norflurazon-treated and normally greening seedlings indicated that at least 57 and 62%, respectively, of alpha-amylase activity was in the apoplast. alpha-Amylase activity recovered from the apoplast of photobleached leaves of norflurazon-treated seedlings was 18-fold higher than that for green leaves. Inhibitors of photosynthesis (DCMU and atrazine) and an inhibitor of chlorophyll accumulation that does not cause photooxidation of plastid components (tentoxin) had little effect on levels of alpha-amylase activity, indicating norflurazon-caused loss of chlorophyll and lack of photosynthesis did not cause the large induction in alpha-amylase activity. An inhibitor of both abscisic acid and gibberellin synthesis (paclobutrazol [PP333]) and an analog of norflurazon which inhibits photosynthesis but not carotenoid synthesis (San 9785) caused only moderate (about five-fold) increases in alpha-amylase activity. Lincomycin and chloramphenicol increased alpha-amylase activity in light grown seedings to the same magnitude as norflurazon, indicating that the effect of norflurazon is probably through the destruction of plastid ribosomes. It is proposed that chloroplasts produce a negative signal for the regulation of the apoplastic alpha-amylase in pea.

Journal Article↗
PubMed1985

General Biochemical Characterization of Thermostable Extracellular beta-Amylase from Clostridium thermosulfurogenes.

Clostridium thermosulfurogenes, an anaerobic bacterium which ferments starch into ethanol at 62 degrees C, produced an active extracellular amylase and contained intracellular glucoamylase but not pullulanase activity. The extracellular amylase was purified 2.4-fold, and its general physicochemical and catalytic properties were examined. The extracellular amylase was characterized as a beta-amylase (1,4-alpha-d-glucan maltohydrolase) based on demonstration of exocleavage activity and the production of maltose with a beta-anomeric configuration from starch. The beta-amylase activity was stable and optimally active at 80 and 75 degrees C, respectively. The pH optimum for activity and the pH stability range was 5.5 to 6 and 3.5 to 6.5, respectively. The apparent [S](0.5V) and V(max) for beta-amylase activity on starch was 1 mg/ml and 60 U/mg of protein. Similar to described beta-amylase, the enzyme was inhibited by p-chloromercuribenzoate, Cu, and Hg; however, alpha- and beta-cyclodextrins were not competitive inhibitors. The beta-amylase was active and stable in the presence of air or 10% (vol/vol) ethanol. The beta-amylase and glucoamylase activities enabled the organism to actively ferment raw starch in the absence of significant pullulanase or alpha-amylase activity.

Journal Article↗
PubMed1986

Culture Conditions for Production of Thermostable Amylase by Bacillus stearothermophilus.

Bacillus stearothermophilus grew better on complex and semisynthetic medium than on synthetic medium supplemented with amino acids. Amylase production on the complex medium containing beef extract or corn steep liquor was higher than on semisynthetic medium containing peptone (0.4%). The synthetic medium, however, did not provide a good yield of extracellular amylase. Among the carbohydrates which favored the production of amylase are, in order starch > dextrin > glycogen > cellobiose > maltohexaose-maltopeptaose > maltotetraose and maltotriose. The monosaccharides repressed the enzyme production, whereas inositol and d-sorbitol favored amylase production. Organic and inorganic salts increased amylase production in the order of KCI > sodium malate > potassium succinate, while the yield was comparatively lower with other organic salts of Na and K. Amino acids, in particular isoleucine, cysteine, phenylalanine, and aspartic acids, were found to be vital for amylase synthesis. Medium containing CaCl(2) 2H(2)O enhanced amylase production over that on Ca -deficient medium. The detergents Tween-80 and Triton X-100 increased biomass but significantly suppressed amylase synthesis. The amylase powder obtained from the culture filtrate by prechilled acetone treatment was stable over a wide pH range and liquefied thick starch slurries at 80 degrees C. The crude amylase, after (NH(4))(2)SO(4) fractionation, had an activity of 210.6 U mg. The optimum temperature and pH of the enzyme were found to be 82 degrees C and 6.9, respectively. Ca was required for the thermostability of the enzyme preparation.

Journal Article↗
PubMed1981

Interaction of human alpha-amylases with inhibitors from wheat flour.

The interaction of four purified alpha-amylase (1,4-alpha-D-glucan glucanohydrolase, EC 3.2.1.1) inhibitors with human salivary and pancreatic alpha-amylases was investigated. The inhibitory activity of the four proteins towards salivary alpha-amylase was significantly increased by pre-incubation of the enzyme with inhibitor before adding substrate. This effect was not observed with the inhibition of pancreatic alpha-amylase by inhibitors 1 and 2. Inhibition of both amylases was affected to different degrees by incubating starch with inhibitor prior to the addition of enzyme. Maltose, at concentrations which only slightly affected amylase activity, prevented the inhibition of both enzymes by all four inhibitors. Gel filtration studies on salivary amylase-inhibitor mixtures showed the formation of EI complexes on a mol-to-mol ratio. A similar complex between pancreatic alpha-amylase and inhibitor 4 was observed, though complex formation between pancreatic alpha-amylase and the other inhibitors was not clearly demonstrated.

Amylases↗