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Factor H is a dermatan sulfate-binding protein: identification of a dermatan sulfate-mediated protease that cleaves factor H.

Dermatan sulfate mediates the blood coagulation cascade by binding to heparin cofactor II and potentiating the antithrombin activity. In order to explore another function of dermatan sulfate, a dermatan sulfate affinity column was prepared from biotinylated dermatan sulfate and Streptavidin Sepharose. When human plasma was applied on the dermatan sulfate column, factor H was bound and cleaved. The cleavage products, a 30-kDa N-terminal fragment and a 120-kDa fragment, were eluted from the column with 500 mM NaCl and detected after Western blotting with anti-factor H. The bond between the tandem arginine residues in the sixth domain of factor H was cleaved. When purified factor H was applied on the column, the factor H was not cleaved and was recovered from the column as an intact 150-kDa fraction. The finding that dermatan sulfate-mediated cleavage of factor H was inhibited by (p-amidinophenyl) methanesulfonyl fluoride, but not N-ethylmaleimide or EDTA, indicates that a serine protease in the plasma was activated on the dermatan sulfate column and factor H was cleaved without intervention of the plasma protease inhibitors. Amidase activity was detected in the effluent from the dermatan sulfate column but was abolished by pretreatment of the plasma with dermatan sulfate. Therefore, dermatan sulfate participates in the activation of a protease as well as having the protease inhibitory action.

Amidohydrolases↗

Raw soybeans stimulate human pancreatic proteinase secretion.

Intraduodenal instillation of raw soybeans stimulated pancreatic proteinase secretion in humans. Raw soybeans almost abolished the activity of chymotrypsin and severely reduced (50%) the tryptic activity. Immunoreactive tryptic and chymotryptic material simultaneously appeared in amounts 2 to 4 times basal concentrations. This increase, demonstrated with rocket immunoelectrophoresis, was begun within the first 10 min of soybean instillation. The enhanced secretion also persisted throughout the succeeding saline instillation, and it is suggested that the presence of Kunitz trypsin inhibitor contributed to this postprandial stimulation. An amidase that hydrolyzes low-molecular-weight substrates (i.e., benzoyl-arginine p-nitroanilide) was found in raw soybeans. Its low activity was not assumed to substantially bias standard trypsin assays. The increased proteinase secretion was, as previously published, not preceded by an elevated plasma cholecystokinin concentration. The raw soybeans also caused a nonparallel secretion of amylase and proteinases. Nervous, perhaps cholinergic, regulation mediates the inhibitor-stimulated proteinase secretion in humans. This stimulation yields both a general increase of proteinases and also a specific inhibitor-resistant trypsin. This is consistent with the physiologic need for proenzyme-activation in the presence of inhibitors and for restoration of the proteolytic capacity of the duodenal juice.

Amylases↗

Purification, staphylolytic activity, and cleavage sites of alpha-lytic protease from Achromobacter lyticus.

Alpha-lytic protease (alp) was purified from a bacteriolytic agent, Achromopeptidase from Achromobacter lyticus M497-1, and has been shown to possess staphylolytic activity. Cleavage sites of this enzyme on the peptidoglycan of Staphylococcus aureus were determined by N-terminal amino acid sequence and amino acid composition analyses. Alp cleaved the N-acetylmuramoyl-L-alanine amide bond, the junction between the polysaccharide and peptide moieties, in addition to the D-Ala-Gly and Gly-Gly peptide bonds, implying that this enzyme recognizes the amino acid of D-configuration at the P1 site and possesses N-acetylmuramoyl-L-alanine amidase activity. However, alp could not cleave the D-Ala-Gly peptide bond in a synthetic peptide, suggesting that this hydrolytic activity of alp is peptidoglycan-specific. The results obtained from different consecutive actions of alp and glycosidase on S. aureus peptidoglycan indicate that the presence of polysaccharide in the peptidoglycan is necessary for the bacteriolytic activity of alp.

Alcaligenes↗

Functional expression of nitrile hydratase in Escherichia coli: requirement of a nitrile hydratase activator and post-translational modification of a ligand cysteine.

The nitrile hydratase (NHase) from Rhodococcus sp. N-771 is a photoreactive enzyme that is inactivated on nitrosylation of the non-heme iron center and activated on photo-dissociation of nitric oxide (NO). The nitrile hydratase operon consists of six genes encoding NHase regulator 2, NHase regulator 1, amidase, NHase alpha subunit, NHase beta subunit and NHase activator. We overproduced the NHase in Escherichia coli using a T7 expression system. The NHase was functionally expressed in E. coli only when the NHase activator encoded downstream of the beta subunit gene was co-expressed and the transformant was grown at 30 degrees C or less. A ligand cysteine, alphaCys112, of the recombinant NHase was also post-translationally modified to a cysteine-sulfinic acid similar to for the native NHase. Although another modification of alphaCys114 could not be identified because of the instability under acidic conditions, the recombinant NHase could be reversibly inactivated by nitric oxide.

Amino Acid Sequence↗

Purification and amino acid sequence of Kunitz-type protease inhibitor found in the hemocytes of horseshoe crab (Tachypleus tridentatus).

A low molecular weight protein protease inhibitor was purified from Japanese horseshoe crab (Tachypleus tridentatus) hemocytes. It consisted of a single polypeptide with a total of 61 amino acid residues. This protease inhibitor inhibited stoichiometrically the amidase activity of trypsin (Ki = 4.60 X 10(-10) M), and also had inhibitory effects on alpha-chymotrypsin (Ki = 5.54 X 10(-9) M), elastase (Ki = 7.20 X 10(-8) M), plasmin, and plasma kallikrein. However, it had no effect on T. tridentatus clotting enzyme and factor C, mammalian blood coagulation factors (activated protein C, factor Xa and alpha-thrombin), papain, and thermolysin. The complete amino acid sequence of this inhibitor was determined and its sequence was compared with those of bovine pancreatic trypsin inhibitor (BPTI) and other Kunitz-type inhibitors. It was found that the amino acid sequence of this inhibitor has a high homology of 47 and 43% with those of sea anemone inhibitor 5-II and BPTI, respectively. Thus, this protease inhibitor appeared to be one of the typical Kunitz-type protease inhibitors.

Amino Acid Sequence↗

Amidolytic activity of porcine trypsin bound to human plasma alpha-1-antiproteinase.

Human plasma alpha-1-antiproteinase interacted with porcine trypsin in two different manners. One was a well known interaction, which resulted in inhibition of the proteolytic activity of the trypsin. The other has not been described to date, and resulted in retention of the amidolytic activity of the trypsin towards benzoyl-L-arginine p-nitroanilide in the presence of soybean trypsin inhibitor. The latter, so-called trypsin-protein amidase, activity is essentially the same as that observed with vertebrate alpha-macroglobulin and rodent murinoglobulin under similar conditions. All attempts to separate the two different activities as well as to abolish either activity by means of chemical or physical modifications were unsuccessful. The proteolysis-inhibiting interaction, which was virtually completed within 5 min, was predominant over the amidolysis-retaining interaction, when the inhibitor/trypsin molar ratio was less than 1. On the other hand, the amidolysis-retaining interaction, which proceeded much more slowly, became evident when the molar ratio was greater than 1.

Amidohydrolases↗

Partial purification and characterization of sialate O-acetylesterase from bovine brain.

From bovine brain an esterase was purified 2,600-fold in an overall yield of 5.6%. For the isolation ion-exchange chromatographies, gel filtration, and preparative isoelectric focusing were used. The molecular mass is 56 kDa after gel chromatography on Sephacryl S-200 and 51 kDa after HPLC, the pH-optimum at 7.4, and the isoelectric point in the range of pH 5.8-6.1, as estimated from preparative isoelectric focusing. The substrate specificity of this enzyme was tested with various naturally occurring O-acylated sialic acids, synthetic carbohydrate acetates, and other esters. Besides aromatic acetyl esters such as e.g. alpha-naphthyl acetate, the highest preference was for N-acetyl-9-O-acetylneuraminic acid, followed by N-acetyl-4-O-acetylneuraminic acid. Other primary acetyl esters such as 6-O-acetylated D-glucose and 2-acetamido-2-deoxy-D-mannose were not hydrolyzed. The 9-O-acetyl derivative of the naturally occurring unsaturated sialic acid 2-deoxy-2,3-didehydro-N-acetylneuraminic acid, however, is a substrate for this esterase. Whereas N-acetyl-9-O-acetylneuraminic acid as a component of sialyllactose is nearly as well hydrolyzed as the corresponding free sialic acid, O-acetylated sialoglycoconjugates with high molecular weights (mucins, serum glycoproteins, gangliosides) are not hydrolyzed by this esterase. N-Acetylated sialic acids are better substrates than the analogous N-glycoloyl derivatives. Esterification of the carboxyl function of sialic acids prevents the action of the esterase on the O-acetyl groups. The enzyme has no carboxyl esterase or amidase activity, and does not act on acetylcholine. It hydrolyzes almost exclusively acetyl esters. Inhibition studies suggest that it has a catalytically active serine residue.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylesterase↗

Hamster alpha-macroglobulin and murinoglobulin: comparison of chemical and biological properties with homologs from other mammals.

alpha-Macroglobulin and murinoglobulin were purified to homogeneity from Syrian hamster plasma and their properties were compared with those of their respective homologs from other mammals. The trypsin-inhibiting capacity of hamster murinoglobulin was much weaker than those of rat and mouse murinoglobulins. Hamster alpha-macroglobulin was cleaved by trypsin at a number of sites whereas the human homolog was split essentially only in a "bait" region into two fragments of similar size. Hamster alpha-macroglobulin treated with methylamine differed from that treated with trypsin in the electrophoretic mobility, intensity of fluorescence induced by binding of bis(8-anilino-1-naphthalenesulfonate), and plasma clearance pattern, whereas virtually no difference was observed between the human homologs treated in the same manner. The reaction of hamster alpha-macroglobulin with methylamine, as measured by the generation of thiol groups and the decrease in trypsin-protein amidase activity, was much slower than that of the human homolog. Trypsin in a complex with hamster alpha-macroglobulin retained its fibrinolytic activity, but this was not the case for human or rabbit alpha-2-macroglobulin. These results suggest that, compared with the human homolog, hamster alpha-macroglobulin is more loosely packed in the native state, undergoes conformational change more slowly on treatment with methylamine, and less efficiently hinders the access of proteinaceous substrates to trapped proteinase. The serum concentration of hamster alpha-macroglobulin was 6.9 mg/ml, or about 3-fold higher than that of the human type, and showed little change during the acute-phase reaction.(ABSTRACT TRUNCATED AT 250 WORDS)

Amidohydrolases↗

Purification and some properties of cathepsin A of small molecular size from pig kidney.

Cathepsin A [EC 3.4.2.-] of small molecular size (cathepsin A, S) has been purified about 800-fold from pig kidney by procedures including chromatographies on DEAE-Sephadex, SP-Sephadex, and Sephadex G-150. 1. The homogeneity of the purified enzyme was proved by ultracentrifugation and polyacrylamide gel electrophoresis. The molecular weight (100,000) and isoelectric point (pI=5.0) were estimated. 2. The enzyme was remarkably stabilized by sucrose and KCl, and was most stable at pH 5-5.5 in the presence of both stabilizers. The enzyme had not only peptidase activity but also esterase and amidase activity; it was optimally active at pH 5.2 for peptide hydrolysis and at pH 8 for the hydrolysis of esters and amides. 3. Diisopropyl fluorophosphate and iodoacetamide completely inhibited these three activities. 4. The enzyme hydrolyzed various benzoyl- and benzyloxycarbonyl-dipeptides with neutral, acidic, and basic amino acids, and proline in the C-terminal position. The carboxypeptidase nature of the enzyme was proved by its action on an oligopeptide. 5. Several enzymatic properties of cathepsin A, S were almost the same as thoas of cathepsin A of large molecular size (cathepsin A, L) and the crude homogenate.

Animals↗

Alkaline serine proteinases D and E of Streptomyces griseus K-1.

Two DFP-sensitive alkaline proteinases with strong esterase activity toward Ac-(Ala)3-OMe, designated as alkaline serine proteinases D and E, were purified pronase, a protease mixture from St. griseus K-1. Each was shown to be homogeneous by acrylamide disc gel electrophoresis. The molecular weights of these enzymes were estimated to be about 27,000 be gel filtration. Studies on their actions on acyl-tl-amino acid methyl or ethyl esters indicated that proteinases D and E both exhibited a broad substrate specificity and hydrolyzed the ester bonds of esters containing Trp, Tyr, Phe, Leu, and Ala. The esterase activities of both enzymes toward Ac-(Ala)3-OMe were the highest among proteinases so far isolated from various sources. Proteinases D and E also lacked cystine residues in their molecules, being entirely different from alkaline serine proteinases A, B, and C in pronase. Some differences were , however, observed between them as regards pH stability, behavior on CM-cellulose, mobility on polyacrylamide electrophoresis, and amidase activity toward Suc-(Ala)3-pNA.

Hydrogen-Ion Concentration↗

Purification and characterization of a coagulant enzyme from Trimeresurus flavoviridis venom.

An enzyme bearing thrombin-like specificity has been purified to homogeneity from the venom of Trimeresurus flavoviridis (the Habu snake). The enzyme is a monomer with a molecular weight of 23,500 as determined by analytical gel filtration and sodium dodecyl sulfate polyacrylamide gel electrophoresis. The protein contains approximately 210 amino acid residues and has a relatively high content of aspartic acid and glutamic acid. The isoelectric point was 4.8 and the extinction coefficient at 280 nm for a 1% solution was 11.5. The enzyme acted directly on fibrinogen to form a fibrin clot with 2.0 NIH units. Analysis by high performance liquid chromatography of enzyme-treated fibrinogen revealed the release of a peptide identical in composition to thrombin-induced fibrinopeptide A, but no peptide corresponding to fibrinopeptide B was detected. The enzyme showed esterase and amidase activities on synthetic substrates containing arginine. The enzyme exhibited higher activity toward tosyl-L-arginine methyl ester (TAME) but 6-times lower activity toward benzoyl-L-arginine p-nitroanilide when compared with bovin thrombin. The esterase activity was inhibited by diisopropylfluorophosphate and at a slower rate by phenylmethanesulfonyl fluoride, but was least affected by tosyl-L-lysine chloromethyl ketone, showing that the enzyme is a serine protease like thrombin. The enzyme showed a bell-shaped pH dependence of kcat/Km for hydrolysis of TAME, with a maximum around pH 8.5.

Amino Acids↗

Isolation and characterization of alpha-macroglobulin from guinea pig plasma.

Guinea pig alpha-macroglobulin was purified to apparent homogeneity by sequential chromatography on Sephacryl S-300, DEAE-cellulose, and hydroxyapatite. A molecular weight of 780,000 was obtained by equilibrium sedimentation. The preparation migrated as a single band of Mr = 180,000 in sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions. Rabbit antiserum raised against the final preparation partially cross-reacted with human and rat alpha-2-macroglobulins but not with rat alpha-1-macroglobulin. Guinea pig alpha-macroglobulin stimulated the amidolytic activity of trypsin towards a small substrate, but inhibited the proteolytic activity of trypsin towards remazol brilliant blue hide powder. When treated with trypsin or methylamine, four thiol groups per molecule were newly generated. The reaction with trypsin proceeded with at least at two different rates: half of the thiol groups were generated in a fast reaction and the remaining half in a slower reaction. On the other hand, such a two-step reaction was not detected in the reaction with methylamine. The methylamine-treated alpha-macroglobulin retained half the capacity to bind trypsin and its mobility in polyacrylamide gel under nondenaturing conditions remained virtually unchanged. These properties are in marked contrast to those reported for human alpha-2-macroglobulin, but resemble those of rat alpha-2- and mouse alpha-macroglobulins. The amidase activity of trypsin bound to guinea pig alpha-macroglobulin was impaired by soybean trypsin inhibitor to a much greater degree than that of trypsin bound to human or rat alpha-2-macroglobulin.

Animals↗

Localization of a proteolytic enzyme within the efferent and deferent duct epithelial cells of the turkey (Meleagris gallopavo) using immunohistochemistry.

Turkey seminal plasma contains a serine protease found to be distinct from the spermatozoal acrosin. However, the origin and biological roles of this enzyme are unknown. Our experimental objective was to identify the cellular source of this protease within the male reproductive tract. The enzyme was isolated from seminal plasma using benzamidine-Sepharose 6B chromatography. A synthetic substrate, Nalpha-benzoyl-DL-arginine p-nitroanilide, was used to detect fractions containing the enzyme. The affinity chromatography technique yielded a 150-fold increase in amidase activity. Analysis of the protease by SDS-PAGE revealed two protein bands with relative molecular masses of 37 000 and 61 000. Proteolytic activity was detected within the smaller band as evidenced by casein digestion. Further analysis of the purified protein revealed that the smaller protein band was glycosylated. To determine the cellular source of the protease, a panel of mouse monoclonal antibodies was then developed against the purified protease, and used in immunohistochemistry. Frozen tissue sections from the liver, testis, epididymal region, and deferent duct were fixed in 4% (w/v) paraformaldehyde, permeabilized with 0.2% (v/v) (octylphenoxy)polyethoxyethanol followed by routine immunohistochemistry procedures. Monoclonal antibodies did not bind to tissue sections from either the liver or testis, or to blood plasma proteins. Both the distal portion of the efferent duct and the deferent duct were immunoreactive. We concluded that the protease found in turkey seminal plasma is concentrated to the distal efferent duct and the deferent duct epithelial cells.

Animals↗

Overpassing an aberrant V(kappa) gene to sequence an anti-idiotypic abzyme with (beta)-lactamase-like activity that could have a linkage with autoimmune diseases.

A monoclonal antibody 9G4H9 that exhibits a beta-lactamase-like activity was previously obtained in accordance with the idiotypic network theory. This abzyme presents the most catalytic efficiency in amidase activity described in literature (kcat = 0.9 min-1). Some reports have demonstrated that functionality as complex as catalysis may be mimicked in this way. Comparison of the catalytic properties of both enzyme and abzyme previously allowed us to obtain better knowledge about 9G4H9 abzymatic machinery. In attempt to characterize this abzyme, the variable regions of kappa and heavy chain were cloned. We present a 'universal' method to clone the correct Vkappa gene to bypass aberrant Vkappa (abVkappa) produced by MOPC-21-derived hybridomas. Sequences obtained are compared in the GenBank database. The VH and Vkappa genes present some important sequence homology with autoantibodies suggesting a direct relationship between catalytic anti-idiotypic antibody and autoimmunity.

Amino Acid Sequence↗

Dopaminergic properties and experimental anti-parkinsonian effects of IPX750 in rodent models of Parkinson disease.

With a view toward improving the neural bioavailability of administered dopaminergic compounds, including dopamine, synthetic efforts have been directed toward enhancing the brain bioavailability of these compounds by accessing cellular sugar transport systems with stereoselective dopaminergic drugs. While synthesis and chemistry of the resultant class of compounds has recently been described in US Patent No. 6,548,484, the associated biologic properties have not previously been reported. One member of this new class, IPX-750, is a pro-drug dopamine-gluconamine designed to retain stereospecificity of binding at: glucose transporters (GLUT 1/GLUT 3 and intestinal Na/glucose co-transporters SGLT1), dopamine transporter (DAT); and, dopaminergic receptors of the D1/D2 families. Designed to be cleavable by tissue amidases, results reported here show that intact IPX-750 pro-drug retains dopaminergic agonist binding and biologic activities both in vitro and in vivo. IPX-750, like dopamine, exhibited predominant D5/D1 binding specificity with lower binding activity at D2. As expected, binding was highly stereo-specific, ie, IPX-760, a benzamide differing in just a hydrogen atom and keto oxygen from IPX-750, bound with 6-fold lower activity at D5. In cell culture, activation resulted from binding of IPX-750 at D1 or D5 in transfected cells was measured by increased intracellular cAMP. Interestingly, considering prior reported in vitro toxicity of dopamine oxidized and metabolic product dopamine, no evidence of in vitro toxicity was observed at up to 72 hrs in cell cultures at the EC50 of IPX-750 for increasing intracellular cAMP. IPX-750 was evaluated in the Parkinson's disease animal models, including MPTP mouse model, the 6-hydroxydopamine (6-OHDA) rat model and the Nurr1(+/-) knockout mouse model. In MPTP-lesioned and Nurr1+/- knockout mice, IPX-750 significantly increased Rota-rod time. In 6-OHDA-lesioned rats, IPX-750 significantly decreased apomorphine (APO)-induced rotation. Worthy of note, after cessation of IPX-750 treatments the anti-parkinsonian activity in MPTP-lesioned and Nurr1+/- mice required about 2 weeks to washout, suggesting a possible biologic reservoir of drug. In addition, after eight weeks of twice daily administration of 20 mg/kg IPX-750, mice did not show statistical difference in the total number of TH-positive neurons in substantia nigra (SN). These combined results suggest (i) that stereo-specific glycoconjugation may be an effective method to improve penetrability of drugs through the blood brain barrier; (ii) treatment with bioavailable IPX-750 in vitro did not show evidence for neurotoxicity; and, (iii) IPX-750 possesses dopaminergic properties and exerts anti-parkinsonian effects in three different PD rodent models, suggesting therapeutic potential for this new class of drugs in treating dopamine deficiency diseases.

Animals↗

Therapeutic effects of continuous intraarterial antibiotic infusion in preventing pancreatic infection in experimental acute necrotizing pancreatitis.

To determine the efficacy of antibiotics in the prevention of pancreatic infection and the process of aggravation after induction of acute pancreatitis, antibiotic was administrated intravenously or intraarterially, starting 6 h after acute pancreatitis was induced in dogs by injecting autologous gallbladder bile into the main pancreatic duct. Flomoxef, recognized as an antibiotic able to penetrate well into pancreas tissue, was selected for the present study. Animals were divided into three groups: no antibiotic given (Group A), antibiotic given intravenously as a bolus injection of 25 mg/kg every 6 h (Group B), and antibiotic infused continuously into the celiac trunk (4 mg/kg/h) (Group C). Compared with Group A, continuous intraarterial infusion of antibiotic (Group C) significantly improved the survival rate and decreased the serum levels of phospholipase A2(PLA2) activity and endotoxin. Furthermore, it completely prevented the occurrence of pancreatic infection, not only ameliorating the severity of pancreatic necrosis but also reducing the activity levels of amidase, trypsin-like enzyme, and PLA2 in pancreas tissue. Group B showed little beneficial effect. Antibiotic concentration in peripheral blood and pancreas tissue was significantly higher in Group C than in Group B. These results suggest that continuous arterial infusion of antibiotics into the feeding artery of the pancreas is an effective modality for preventing pancreatic infection and aggravation of severe acute pancreatitis.

Amidohydrolases↗

Experiments in microbial evolution: new enzymes, new metabolic activities.

Biological evolution has resulted in a richness and diversity of species. Among microorganisms this is most evident in the wealth and diversity of biochemical transformations. Evidence for evolutionary relationships may be obtained from comparative studies, but with microorganisms it is also possible to follow evolution in action. Microbial populations adapt rapidly to changes in the environment and the evolution of new metabolic activities can be observed in laboratory experiments. The enzymes of many catabolic pathways are synthesized in response to the presence of inducing substrates. New catabolic activities may be acquired by mutations in regulatory genes resulting in alterations in the specificity of induction, or in enzyme synthesis in the absence of inducer. Mutations in structural genes may given rise to enzymes with altered substrate specificities. In bacteria, catabolic genes may be carried on plasmids and the exchange of plasmids among bacterial populations increases the evolutionary potential. Experiments in microbial evolution have produced strains with novel catabolic activities involving regulatory or structural gene mutations, gene duplications and plasmid exchange. Enzymes studied in this way include amidase, ribitol dehydrogenase, evolved beta-galactosidase, and enzymes of the catabolic pathways for pentoses and pentitols and haloaromatic compounds.

Amidohydrolases↗

Recommended minimal standards for description of new staphylococcal species. Subcommittee on the taxonomy of staphylococci and streptococci of the International Committee on Systematic Bacteriology.

In accordance with Recommendation 30b of the International Code of Nomenclature of Bacteria, minimal standards are proposed for the genus Staphylococcus and the description of newly recognized species in this genus. Assignment of a strain to the genus Staphylococcus requires that it is a Gram-positive coccus that forms clusters, produces catalase, has an appropriate cell wall structure (including peptidoglycan type and teichoic acid presence) and G + C content of DNA in a range of 30-40 mol%. The recommended minimal standards for describing a new Staphylococcus species are based on the results of phenotypic and genomic studies of at least five independently isolated strains. They include colony morphology and the results of the following conventional tests: pigment production, growth requirements, fermentative and oxidative activity on carbohydrates, novobiocin susceptibility, enzymic activities (nitrate reductase, alkaline phosphatase, arginine dihydrolase, ornithine decarboxylase, urease, cytochrome oxidase, staphylocoagulase in rabbit plasma, heat-stable nuclease, amidases, oxidases, clumping factor, and haemolytic activity on sheep or bovine blood agar). DNA-DNA hybridization experiments may distinguish species when the difference between the binding in the homologous reaction and the binding in the heterologous reaction expressed as a percentage is less than 70%. In addition, rRNA signature sequence criteria, ribotyping characterization of the nomenclature type strain and other strains of the species, and reference strains of other species is recommended to describe the strains of the new species with sets of genetic attributes and reveal possible grouping errors. This proposal has been endorsed by the members of the Subcommittee on the taxonomy of staphylococci and streptococci of the international Committee on Systematic Bacteriology.

Animals↗