Serial studies of the serum levels of trypsin inhibitor have been performed on monkeys following injection of turpentine-falba, total body irradiation, thermal injury, splenectomy, administration of cortisone acetate and egg albumin. Following the injection of turpentine-falba mixture there was a prompt elevation in the trypsin inhibitor power of the serum. A similar response accompanied the ad...

The present study was designed to determine whether renal prostaglandins are involved in the renal vasodilation evoked by angiotensin II inhibition in sodium depletion. The converting enzyme inhibitor (CEI) captopril was administered to sodium-depleted control dogs and sodiumdepleted dogs that had previously received the inhibitors of prostaglandin synthesis, indomethacin or meclofenamate. CEI ...

Enzymes that degrade cellulose into glucose are one of the most expensive components of processes for converting cellulosic biomass to fuels and chemicals. Cellulase enzyme Cel7A is the most abundant enzyme naturally employed by fungi to depolymerize cellulose, and like other cellulases is inhibited by its product, cellobiose. There is thus great economic incentive for minimizing the detrimenta...

Pyruvate kinase (EC 2.7.1.40) is inhibited by phenethylbiguanide. The kinetics of inhibition are competitive between biguanide and divalent, but not monovalent, metal cation activators of the enzyme; biguanide inhibition thus resembles inhibition by Ca(++). Alteration of either the polar or nonpolar portion of the phenethylbiguanide molecule quantitatively reduces its effectiveness as an inhibi...

The potential antihypertensive activity of Brazilian plants was evaluated in vitro by its ability to inhibit the angiotensin-converting enzyme (ACE). Forty-four plants belonging to 30 families were investigated. Plants were selected based on their popular use as antihypertensive and/or diuretics. The following plants presented significant ACE inhibition rates: Calophyllum brasiliense, Combretum...

Addition of 2 mg of Pb2+/g of soil concident with or after amendment with starch or maltose resulted in 75 and 50% decreases in net synthesis of amylase and alpha-glucosidase, respectively. Invertase synthesis in sucrose-amended soil was transiently reduced after Pb2+ addition. Amylase activity was several times less sensitive to Pb2+ inhibition than was enzyme synthesis. In most cases, the rat...

Angiotensin converting enzyme (ACE) inhibitors have been available for the treatment of hypertension and heart failure for several years. This class of drugs is generally well accepted by the patient (1), but an unusual, infrequent, and troublesome side-effect, cough, has become apparent. This article reviews this side-effect and also the possibility of other respiratory effects of ACE inhibition.

It is widely accepted that urea and guanidine act as protein denaturants by breaking intramolecular hydrogen bonds (1). Loss of catalytic activity in the presence of urea is thought to occur by elimination of bonds contributing to the tertiary structure of enzyme molecules. Subsequent restoration of structural and catalytic properties by removal of the denaturant, “reversible denaturation,” is ...

A study of the inhibition of the growth of Streptococcus cremoris 972 by the enzyme lactoperoxidase has shown, in agreement with previous investigations, that the inhibition requires a source of both peroxide and thiocyanate. The thiocyanate may play more than one role. It stabilizes the very dilute solutions of lactoperoxidase employed in these studies, and its oxidation products may be involv...