text stringlengths 2 5.29k |
|---|
An isolated perfused canine lung preparation in which determinants of vascular caliber could be individually controlled was developed. The relation of pulmonary arterial (Pa), venous (PV), and alveolar (PA) pressures was such that Pa greater than PA greater than PV throughout the whole lung. The addition of isoprenalin... |
The interaction of chemoreflex and pulmonary inflation reflex control of the coronary circulation was examined in conscious dogs by comparing the responses to chemoreflex stimulation (intracarotid injection of nicotine) when ventilation was allowed to increase with those when ventilation was controlled. The responses w... |
The rate of coronary blood flow was varied in isolated working rat heart preparations to determine its influence on the rate of glocose utilization, tissue high-energy phosphates, and intracellular pH. A 60% reduction in coronary blood flow resulted in a 30% reduction in oxygen consumption, an accelerated rate of gluso... |
The mechanisms of glycolytic inhibition in ischemic myocardium were investigated in the isolated, perfused rat heart. Glycolysis was inhibited at the level of glyceraldehyde-3-phosphate dehydrogenase. The major factors that accounted for the glycolytic inhibition in the ischemic heart compared with the anoxic heart app... |
This study compared the contractile performance of a canine right atrial trabecula with that of a macroscopically indistinguishable trabecula isolated from the right ventricular apex. The heart was removed from nine mongrel puppies weighing 6-8 kg and placed in Krebs-Ringer's bicarbonate solution. The bathing solution ... |
1. The lactate dehydrogenase activity of 89 sera from patients suffering myocardial infarction and of 55 sera from patients with hepatocellular damage was assayed under optimal conditions using pyruvate, alpha-oxobutyrate, hydroxypyruvate and glyoxylate as substrates. Activity was also measured with lactate as substrat... |
We describe a simple, rapid fluorometric assay for separate quantitative analysis of procainamide and N-acetylprocainamide in mixtures. The effective lenear range (fluorescence vs. concentration) in serum is 0.1 to 10.0 mg/liter, regardless of the ratio (by weight) of the two drugs from 1:10 to 10:1. Analytical recover... |
In this method, blood is collected in ammonium heparinized microhematocrit tubes and lactate is directly determined in the plasma, separated within 15 min from the erythrocytes. Lactate is assayed by mixing 10 mul of sample with NAD+ and lactate dehydrogenase in tris(hydroxymethyl)aminomethane hydrazine buffer. The rat... |
High-voltage paper electrophoresis of small samples of serum and urine at pH 6.0 resolves basic and acidic amino acids and separates them from the neutral amino acids. For separation and identification of the neutral amino acids, the appropriate area of the electrophoretogram is cut out, sewn onto a second sheet of pap... |
A simple, highly sensitive and reproducible method for the assay of gamma-glutamyl transpeptidase (EC 2.3.2-) activity is introduced, using gamma-glutamyl-p-nitroanilide as a substrate and glycylglycine as an acceptor in 50 g/l of polyoxyethylene nonylphenol. Serum transpeptidase activity was assayed in 1080 healthy ad... |
There are different types of renal hypertension: hypertension due to parenchymal renal disease, renovascular hypertension, hypertension due to urological disease, hypertension of endstage renal disease. Treatment has to consider-above all-the possibility of specific, medical or surgical procedures that may cause the un... |
1. Some effects of sodium salicylate upon anaerobic glycolysis have been studied in normal human erythrocytes incubated for up to 6 h at 37 degrees C in autologous sera. 2. Both glucose consumption and lactate production were stimulated by concentrations of salicylate up to 60 mmol/l but at the highest concentration us... |
1. We measured the minute ventilation and arterial blood catecholamine concentrations in four normal men standing and at two levels of moderate treadmill exercise breathing 14% oxygen or air. 2. Minute ventilation was significantly higher during hypoxic exercise than during normoxic exercise at an oxygen uptake of 1500... |
In 4 dogs injected intravenously (i.v.) with 125I labeled fibrinogen, 51Cr labeled platelets and 99mTc labeled albumin, and subjected to successively increasing amounts of i.v. infused monomethylmethacrylate, doses corresponding to the amounts released into the blood stream following implantation of acrylic cement duri... |
Clinical impressions about the problem of defibrillation during states of acid-base imbalance and hypoxia have been influenced by studies involving the effect of these derangements on the ventricular fibrillation threshold. Based on body weight, energy requirements for defibrillation in normal dogs were compared to req... |
A patient with aortitis syndrome had a pleural effusion which subsided but reappeared with an exacerbation of aortitis symptoms while under antituberculosis treatment. The character of the fluid was that of an exudate, and the glucose concentration was normal. Clinical and laboratory features of the case suggest that t... |
At the Department of Plastic Surgery and Burns, Berufsgenossenschaftliche Unfalklinik Ludwigshafen-Oggersheim, a skinbank with typed skin has been established. The storage system consists of deep-freezing at -196 degrees C in liquid nitrogen. The transplantation of HL-A typed skin was evaluated from the clinical and hi... |
The apparent isoelectric points (pI) in isoelectric focusing (IF) of human pituitary and amniotic fluid prolactin (hPRL), both non-iodinated and iodinated, were determined. Unresolved mixtures of pituitary hPRL isohormones E and F, and of at least five isohormones found in amniotic fluid, and plasma hPRL exhibit an ave... |
The feasibility of using isoelectric focusing for the separation of primate pituitary growth hormone from prolactin and for the characterization of polymorphic forms of these hormones was explored. In a pH 3--10 gradient, extracts of both human and cynomolgus monkey pituitaries were each resolved into 4 growth hormone ... |
Certain climatic and edaphic conformations in the Bavarian sub-alpine mountains and in the Alps favor above all the development of a land utilization system and farm structures similar to those in the northern part of Scandinavia. In 1963/64, the years of the highest environmental contamination up to the present, we es... |
Both UDP-glucuronyltransferase (GT) and beta-glucuronidase (betaG) were assayed in untreated liver microsomes. Optimum assay conditions were established with rat liver microsomes using p-nitrophenol (pNP) and its glucuronide (pNPGA) at the pH optima of GT (7.5) and betaG (4.5). The activities of the two enzymes were co... |
In omnivorous creatures, the diet is acidogenic, especially as a result of the meat content, which gives rise to phosphoric and sulphuric acids, i.e., to metabolic acidosis. In the short term, metabolic acids are buffered by tissue proteins and bicarbonate (the 'alkali reserve'). In the longer term, acid must be excret... |
Serum, liver and renal gamma-glutamyl transpeptidase (GGT) activities were studied in four groups of rabbits: controls, rabbits with obstructive extrahepatic cholestasis, rabbits with obstructive anuria, and animals with combined obstructive extrahepatic cholestasis and obstructive anuria. Serum GGT was essentially inc... |
The mechanism responsible for the changes in serum and liver gamma-glutamyl transpeptidase (gamma-GT) activity was studied in a model of experimental hexachlorobenzene porphyria in rabbits. Porphyria followed the administration of hexachlorobenzene in doses of 280 mumol - kg-1 body weight, which were given daily throug... |
15 untrained women were subjected to a walking treadmill test to determine the influence of maximal exercise upon synthesis of erythrocyte 2,3 DPG. Although there was a 9.8% increase in the 2,3 DPG content following exercise, there was a concomitant 9.4% increase in the hemoglobin level; therefore, when 2,3 DPG is expr... |
1. Chloroplasts isolated from leaves of spinach-beet (Beta vulgaris L. ssp. vulgaris) do not catalyse the hydroxylation of p-coumaric acid in the dark unless a reductant (such as ascorbate, NADH or NADPH) is added. Superoxide dismutase has no effect on this reaction. 2. Illuminated chloroplasts catalyse the hydroxylati... |
35Cl minus-nuclear magnetic resonance (NMR) studies indicate that various digests of human hemoglobin with carboxypeptidase A and B, or a combination of the two, may be used for the identification of chloride binding sites. All the digestion products contain, like hemoglobin itself, at least two classes of binding site... |
1. The intracellular pH was measured in growing Clostridium pasteurianum with and acid-base equilibrium distribution method. [14C]Dimethyloxazolidinedione, [14]methylamine and [14C]acetic acid were used as "deltapH-indicators". During growth the extracellular pH decreased from 7.1 to 5.1; simultaneously the intracellul... |
Membranes of the bacterial form and the stable and unstable L-forms of Proteus mirabilis contain LD and DD-carboxypeptidase. The DD-carboxypeptidase is inhibited non-competitively by penicillin G. The enzyme of the bacterial form is highly penicillin-sensitive (Ki - 4 X 10(-9) M penicillin G). Inhibition is only partly... |
NAD kinase was purified from pigeon liver by an improved procedure which included chromatography on phosphocellulose. The resultant preparation was homogeneous as judged by gel electrophoresis, but electrofocusing gave indications of heterogeneity. The enzyme appeared to be of molecular weight 270000, and to consist of... |
The effect of acid-base alterations was analyzed using isolated rat hearts perfused at constant coronary perfusion pressure, and stimulated to contract at constant rat. The amount of shortening in the major axis and its derivative were measured to assess myocardial contractility. Both the 'respiratory' and 'metabolic' ... |
21 patients with cirrhosis of the liver and 24 control patients were studied before and after a protein load (120 g protein per day during one week). An EEG was recorded and a visual assessment of frequency pattern was performed. Venous admixture was estimated during hyperoxia. According to the EEG frequency pattern th... |
Two main aspects of the in vitro mouse foetal liver cell assay for Erythroid Stimulating Factor (ESF) in human sera have been investigated. The haem extraction process has been shown to give specific and quantitative recovery of 59Fe labelled haem from haemoglobin thus confirming that the material assayed in human sera... |
Some derivatives of isoindoline were prepared in order to test their cardiovascular activity. Pharmacological tests showed that some of the compounds had moderate alpha-blocking and coronarodilatory activity whereas others had some local anesthetic activity. |
In white rats both adapted and unadapted to cold, the RQ dynamics during cold exposure, noradrenaline and ganglion blocking agent administration, were studied. The adapted animals' RQ in thermoneutral conditions was shown to be a little higher than in the control rats; 0.5 mg/kg noradrenaline injections induced a clear... |
A sulfonamide-resistant mutant of pneumococcus, sulr-c, displays a genetic instability, regularly segregating to wild type. DNA extracts of derivatives of the strain possess transforming activities for both the mutant and wild-type alleles, establishing that the strain is a partial diploid. The linkage of sulr-c to str... |
Conditions are described in which the pneumococcal mutant strain sulr-c, resistant to the drug sulfanilamide, gives rise to sensitive segregants resistant to nitrobenzoic acid at a frequency constant with time. This segregant frequency is markedly enhanced upon exposure of the cells to doses of ultraviolet light or mit... |
A patient is reported with mast cell infiltration of the small intestine in the absence of the skin involvement characteristic of mast cell disease. She also had subtotal villous atrophy responsive to a gluten-free diet. Criteria for diagnosing mast cell disease of the small intestine are proposed. The literature of sm... |
The microflora and pH of gastric contents were determined in breast-fed and in bottle-fed normal infants, in well nourished infants with acute diarrhoea and in infants with chronic diarrhoea and protein-calorie malnutrition. The last group of infants was reevaluated after recovery from diarrhoea and protein-calorie mal... |
Adrenaline-induced gastric ulceration was studied in rats. Adrenaline in high doses caused gastric ulcer, which was completely blocked by pretreatment with alpha-blockers (phenoxybenzamine, dibenamine), but not by pretreatment with propranolol or atropine, nor by vagotomy, hypophysectomy or adrenalectomy. After success... |
Adrenaline and isoproterenol elicited nearly maximal relaxation of the colon even in small doses, whereas increase in the doses caused greater relaxation in the duodenum. In the colon, these drugs prevented, to a great extent the contraction induced by acetylcholine (ACh) and serotonin but in the duodenum were totally ... |
Enzymic properties of monoamine oxidase (MAO) in dog serum were studied and the following results were obtained. Some of enzymic properties of MAO in dog serum differed from that of mitochondrial MAO. When dog serum was fractionated by ammonium sulfate, proteins were concentrated in two fractions, such as 25 approximat... |
A combination of two or more drugs may exert a drug-drug interaction, in which case the effect can be potentiated or antagonized. Such synergistic effects are well known in the case of pyrabital (barbital + aminopyrine) or irgapyrine (phenylbutazone + aminopyrine). Bucolome (BCP), a non-steroidal anti-inflammatory agen... |
We have already reported that bucolome (BCP), a non-steroidal anti-inflammatory agent, potentiates significantly the analgesic and antipyretic effects of pyrazolones which are substituted by alkylamino group at 4-position of the pyrazolone ring. Physical and quantum chemistry were applied to the mechanism of this syner... |
FDP aldolase was found to be present in the cell-free extracts of Rhizobium leguminosarum, Rhizobium phaseoli, Rhizobium trifolii, Rhizobium meliloti, Rhizobium lupini, Rhizobium japonicum and Rhizobium species from Arachis hypogaea and Sesbania cannabina. The enzyme in 3 representative species has optimal activity at ... |
In the presence of amino sugars D-glucosamine and D-galactosamine no spontaneous competence could be observed in the highly transformable R6bd strain of Pneumococcus or it was decreased by several orders of magnitude. The highest inhibition of competence was detected when the amino sugar at a concentration 5 mg/ml of t... |
The inhibitory effect of molybdenum ions on growth of yeasts at pH 5.5 was found to be decreased by aldoses in the following order: D-talose greater than L-mannose greater than L-ribose greater than D-lyxose greater than L-galactose greater than L-arabinose greater than L-glucose greater than L-xylose. Increased concen... |
The glucose transport system of membrane vesicles isolated from Acholeplasma laidlawii is saturable, with a Km of 21.2 mum and V of 0.68 nmol min-1 (mg protein)-1. The process is pH-dependent and a break occurs in the Arrhenius plot at 15 degrees C. Exogenous substrates did not stimulate glucose transport probably due ... |
Tritium-labelled 4-deoxy-D-glucose (4-dglc) and 6-deoxy-D-glucose (6-dgcl) were prepared by catalytic hydrogenolysis of the corresponding deoxyiodo derivatives with gaseous tritium. The two sugars are transported into Saccharomyces cerevisiae by both the constitutive glucose and the inducible galactose carrier. Uranyl ... |
Twenty-five Penicillium species isolated from Egyptian soil were examined for their ability to produce gluconic acid in surface culture. Of the eight species capable of producing gluconic acid, Penicillium puberulum gave the maximum yield (91% gluconic acid from glucose after 7 days of fermentation with 3% CaCO3). Pept... |
A simple method of isolation and purification of cultures of higher fungi, mainly wood-rotting fungi, without special requirements for the presence of nitrogencontaining nutrients is described. Parts of fruiting bodies, spores or infected wood is inoculated on Petri dishes with an agar medium of the following compositi... |
This report concerns the feasibility of low volume priming extracorporeal circulation. Through this study, the bubble oxygenator with Zuhdi's heat exchange was used. Moderate hypothermia with surface cooling and hemodilution perfusion with 5 per cent D/W was evaluated in 32 mongrel dogs and 16 clinical open heart cases... |
Twenty mongrel dogs, weighing between 7.5 and 13.0 kg were used to investigate the percentage limits permissible for hemodilution using a double-helical reservoir heart-lung machine which has a 1,100 ml of priming volume. In both 40 and 50 per cent groups of intentional hemodilution by 30 minute extracorporeal circulat... |
A procedure for the purification of phosphodiesterase from Crotalus venom on DEAE-cellulose at alkaline pH is described. The enzyme gives a single band in polyacrylamide gels and is free of contaminating nucleolytic enzymes. The molecular weight is about 115000. Concentration in an Amicon ultrafiltrator gave a highly c... |
Digestion of tRNA by electrophoretically pure phosphodiesterase is limited to a short sequence of nucleotides at the 3'-terminus. On the average, four percent of all nucleotides can be released from tRNA. The optimum Mg2 concentration is 10mM and the optimum pH 9.2. The mode of action is a random attack by the enzyme o... |
In the blowfly, the formation of 3-dehydroecdysone from the insect molting hormone ecdysone is catalyzed by an enzyme which carries hydrogen from ecdysone and ecdysterone to oxygen. The enzyme is therefore called "ecdysone oxidase". Two methods are described for the detection of ecdysone oxidase activity, one using a r... |
An outpatient with phobias related to enclosed places, hospitals, doctors, and cancer was treated by systematic desensitization; the facilities of a general hospital were used for part of the process. Steps in treatment included securing a complete psychiatric and social history, teaching the patient relaxation therapy... |
The kinetics and cellular characteristics of immunosuppression in (CBA-p X C57/Bl)F1 mice during graft-versus-host (GVH) reaction induced with spleen cells from either parental strain have been investigated. Effects on PFC responses to thymus-dependent (chicken red blood cells) and independent (levan) antigens have bee... |
Opsonization of Streptococcus pneumoniae may be mediated by the alternate complement pathway. To study the importance of this interaction to human disease, complement consumption by pneumococci of various serotypes was measured in humwn serum chelated with ethyleneglycoltraacetic acid, a substance that blocks the class... |
Mycobacterial growth inhibitory factor (MycoIF), found in supernatant fluids of mouse spleen cell cultures that have been stimulated in vitro with homologous antigen, inhibited the intracellular multiplication of virulent tubercle bacilli within normal mouse peritoneal macrophages in vitro. Antigenically stimulated H3... |
Infections due to Streptococcus pneumoniae and products from the organism have been associated with alterations in blood clotting and function of platelets. Pneumococci and pneumococcal polysaccharide shortened the clotting times of whole blood, platelet-rich plasma (PRP), and platelet-poor plasma (PPP) in vitro. Clott... |
Envelope preparations of Neisseria gonorrhoeae strain GC1 (a stable, piliated strain of intermediate colony morphology) and type T1 possess a D-alanine carboxypeptidase which releases the terminal alanine residue from the uridine 5'-diphosphate-N-acetyl muramylpentapeptide substrate (isolated from Bacillus cereus T). T... |
Resistance to pneumococcal infection was tested in T-lymphocyte-deficient, nude (nu/nu) mice. Pneumococcal serum opsonizing activity, in vivo phagocytosis of the pneumococcus, and the mean lethal dose for the pneumococcus were all found to be the same in nude mice as in control (+/+) mice. T-lymphocytes do not appear t... |
Staphylococcus aureus produces a phospholipase C specific for sphingomyelin (beta-hemolysin). Erythrocytes with approximately 50% sphingomyelin in their membranes, e.g., from sheep, have been shown to have up to 60% of this phospholipid hydrolyzed by this enzyme at 37 C in isotonic buffered saline without hemolysis. Co... |
PR-D-92-EA was tested on isolated guinea pig ileum and rat stomach strips for activity against mediators probably released after allergen antibody union. It antagonized the response produced by histamine, bradykinin, serotonin, prostaglandin E2, prostaglandin F2ALPHA and slow-reacting substance of anaphylaxis (SRS-A). ... |
Tyrosine aminotransferase (TAT) induction by glucagon and dexamethasone in the liver of tumor-bearing chickens was studied and compared with induction in healthy animals. The transplantable tumor was caused by inoculation of cells from a cell line induced by MC29 avian leukosis virus. TAT was hardly detectable in tumor... |
This paper described a Behavior Modification Training Program, emphasizing self-control, for staff working with drug addicts. The program, which is primarily geared toward the training of paraprofessionals, takes place in ten 1-1/2 hour sessions and includes an overview of behavior modification as well as instruction i... |
Hydrolysis rates of N-acetyl dehydroalanine methyl ester (methyl 2-acetamidoacrylate) and related model compounds were measured in aqueous, organic and mixed aqueous media. Adding dimethylsulfoxide (DMSO) to water, retarded hydrolysis of the ester by a factor of 2 to 500, depending on the pH of the medium and concentra... |
In order for the ophthalmologist to achieve the greatest earning power and personal satisfaction, he or she must devise traffic flow techniques that efficiently allow for maximum utilization of all examining areas and paramedical personnel in the office without dehumanizing patients. By delegating as much responsibilit... |
The spontaneous activity exhibited in vitro by smooth muscle strips from the urinary bladder of the rabbit under the influence of Urecholine in concentrations from 0.3 to 30 muM has been characterized in terms of three parameters: mean tension, frequency of contraction, and contractile deviation, all obtained by comput... |
Non-occluded virions of a nuclear polyhedrosis virus of the alfalfa looper, Autographa californica, found in the medium of cell cultures of infected fall armyworm, Spodopter frugiperda, and in the hemolymph of infected S. frugiperda larvae were partially characterized by biological, chemical and physical methods. Also,... |
Extensively degraded RNA was isolated from virions of influenza virus which had been oxidized with sodium m-periodate. Similarly, although to a lesser extent, RNA isolated from periodate-treated ribonucleoprotein of influenza virus was also degraded. In contrast, influenza virus RNA, if first freed from other virion co... |
Rubella virus failed to replicate in mosquitoes (Aedes albopictus and Culex fatigans) following parenteral inoculation. The virus demonstrated in mosquitoes tested immediately after inoculation but was not detected in insects sampled 7, 14 and 21 days postinoculation. This experiment provides further evidence that rube... |
Minoxidil in daily doses of 6 to 40 mg was administered to 11 patients with severe hypertension. Two patients died of causes unrelated to the drug and one patient withdrew from the study. Blood pressure was controlled in the remaining eight subjects, who received the drug for periods ranging from 5 to 40 months. In thr... |
The secretion of alpha-amylase and electrolytes by the parotid gland is now well understood and similarities exist in this respect between man and animals. Many modern drugs influence parotid secretion and morphology, and these are discussed. |
Acute renal failure is a life-threatening situation for which satisfactory treatment is currently available. Death is usually related to concomitant infection rather than uremia. Prompt recognition and treatment of underlying factors that predispose to renal insufficiency can frequently prevent the development of intri... |
A new esterification procedure was developed to form 2-chloroethyl esters for 10 common herbicidal acids, using dicyclohexyl carbodiimide and 2-chloroethanol. This reagent was found to be more desirable than the commonly used boron trichloride/2-chloroethanol reagent. Maximum esterification was given for picloram at a ... |
Local control of pulmonary resistance and lung compliance was studied in the in situ left lower lobe of the canine lung. Recirculation of blood through the lobe while the Pco2 of the ventilatory gas was varied resulted in an increase in resistance and a decrease in compliance only when the pulmonary venous pH was great... |
A previously unrecognized enzyme, citrate lyase deacetylase, has been purified about 140-fold from cell extracts of Rhodopseudomonas gelatinosa. It catalyzed the conversion of enzymatically active acetyl-S-citrate lyase into the inactive HS-form and acetate. The enzyme exhibited an optimal rate of inactivation at pH 8.... |
The purification and properties of a novel type of murein transglycosylase from Escherichia coli are described. The purified enzyme appears as a single band on sodium dodecyl sulfate-polyacrylamide gels and has an apparent molecular weight of approximately 65,000 as estimated by gel filtration and gel electrophoresis. ... |
2-Keto-3-deoxygluconate aldolase of Aspergillus niger, an enzyme that has not been reported previously, was purified 468-fold. Maximal activity was obtained at pH 8.0 and 50 C. The enzyme exhibited relative stereochemical specificity with respect to glyceraldehyde. The Km values for 2-keto-3-deoxygluconate, glyceraldeh... |
A motile Streptococcus was isolated and its chemotactic behavior toward sugars and amino acids was studied. Motility was optimal in the presence of an exogenous energy source and a nonionic detergent, e.g., Tween 80 or Brij-36. Both glucose and pyruvate could serve as energy source. Chemotaxis toward leucine was optima... |
A phospholipase hydrolyzing cardiolipin to phosphatidic acid and phosphatidyl glycerol was characterized in gram-negative bacteria but was absent in preparations of gram-positive bacteria, Saccharomyces cerevisiae, and rat liver mitochondria. In cell-free extracts of Escherichia coli, Salmonella typhimurium, Proteus vu... |
An alcohol dehydrogenase linked to nicotinamide adenine dinucleotide and requiring glutathione has been isolated and partially purified from two methanol-assimilating yeasts. It differs from previously described methanol-oxidizing enzymes in pH optima, electron acceptor specificity, substrate specificity, inhibition pa... |
The normal hut (histidine utilization) operons, as well as those with mutations affecting the regulation of their expression, of Salmonella typhimurium were introduced on an F' episome into cells of S. typhimurium and Klebsiella aerogenes whose chromosomal hut genes had been deleted and into cells of Escherichia coli, ... |
In merodiploid strains of Klebsiella aerogenes with chromosomal hut genes of K. aerogenes and episomal hut genes of Salmonella typhimurium, the repressor of either species can regulate the hut operons of the other species. The repression exerted by the homologous repressor on the left-hand hut operon is, in both organi... |
The transport of 99MoO42- into dinitrogen-fixing cells of Clostridium pasteurianum was investigated. Transport of molybdate in this organism is energy dependent; sucrose is required in the minimal media, and the system is inhibited by the glycolysis inhibitors, NaF, iodoacetic acid, and arsenate. The cells accumulate m... |
The first committed step of aromatic amino acid biosynthesis in Salmonella typhimurium was shown to be catalyzed by three isoenzymes of 3-deoxy-D-arabino-heptulosonic acid 7-phosphate (DAHP) synthase. Mutations in each of the genes specifying the isoenzymes were isolated and mapped. aroG, the structural gene for the ph... |
A four- to sixfold increase in specific activity of dihydrodipicolinic acid synthase was observed during sporulation of Bacillus cereus. The enzyme from cells harvested before and after the increase in specific activity appeared to be very similar as judged by pH optima, heat denaturation kinetics, apparent Michaelis c... |
The cellular localization of enzymes in Diplococcus pneumoniae was examined by fractionation of spheroplasts. A deoxyribonuclease implicated in the entry of deoxyribonucleic acid (DNA) into the cell during genetic transformation was located in the cell membrane. This enzyme, the major endonuclease of the cell (endonucl... |
D-Lactate dehydrogenase has been purified to near homogeneity from Peptostreptococcus elsdenii. As isolated, the enzyme contains flavine adenine dinucleotide and a tightly bound metal cofactor. Inactivation by ortho-phenanthroline occurs in two steps and is partially blocked by D-lactate. Reactivation by divalent metal... |
Coenzyme A (CoA) transferase from Peptostreptococcus elsdenii has been purified and crystallized, and some of its properties have been established. The work was facilitated by a newly developed coupled and continuous spectrophotometric assay in which the disappearance of added acrylate could be followed at 245 nm. The ... |
Studies were made on the physical and chemical properties of polysaccharides synthesized by cell-free extracts of Streptococcus mutans, Streptococcus sanguis, and Streptococcus sp. and their susceptibilities to dextranases. Among the polysaccharides examined, insoluble glucans were rather resistant to available dextran... |
The synthesis by Streptomyces sp. no. 6 of an extracellular chitosanase was induced by glucosamine. The enzyme was purified to homogeneity by Sephadex G-100, carboxymethyl-cellulose, and diethylaminoethyl-cellulose chromatography. The purified enzyme hydrolyzed chitosan (the beta-1,4-linked polymer of glucosamine) but ... |
After mutagenesis, surviving yeast cells are grown on plates at 25 C and later exposed to 37 C. The plates are then overlaid with a soft agar containing p-nitrophenylphosphate at pH 9.7. Lysed cells liberate alkaline phosphatase which gives rise to a yellow color on and around colonies. |
A deoxyribonuclease, which requires nucleoside triphosphate for reaction, has been purified about 150-fold from extracts of Bacillus laterosporus. Potassium phosphate and ethylene glycol stabilize the purified enzyme. The enzyme degrades double-stranded DNA about 100 times faster than heat-denatured DNA in the presence... |
A radioimmunoassay procedure for guanosine 3',5'-cyclic monophosphate (CGMP) is described. The procedure is based on competitive binding between [3H]CGMP and non-radioactive CGMP, with separation of bound and unbound CGMP by Millipore filtration. The binding reaction showed very high specificity to CGMP, had a broad pH... |
1. Tryptophan was administered to rats under various nutritional conditions: fasted for 24 hr, fasted and refed with glucose or corn-oil, fasted and administered glycerol intramuscularly, and nonfasted. 2. The changes in the contents of glycolytic intermediates in the livers indicated that the phosphoenolpyruvate carbo... |
In order to clarify how the electrophoretic behavior reflects the conformational transition of globular proteins, moving boundary electrophoresis was applied to analysis of the acid conformational change of alpha-lactalbumin. The appearance of only a single electrophoretic boundary in the transition region of the prote... |
The multiple forms of cathepsin A (AI, AII, and AIII) purified from the lysosome fraction of rat liver by Sephadex G-200 and DEAE-Sephadex chromatographies were studied comparatively. Forms AI, AII and AIII were stable between pH 3.0 and 5.5, and had pH optima for CBZ-Glu-Phe at 5.6, 5.8, and 5.9, respectively. These a... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.