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Twelve-day-old rats were fed a mixture of fast and slow chromato-graphically prepared fractions of bovine IgG, labelled with 125I and 131I. The pooled young rat sera were submitted to analysis by electrofocusing. The results show a wide variation of concentration quotients between the different pI peaks of IgG, with the more basic fractions being transmitted more readily in both fractions. One slow IgG peak (pI 7.8) in particular is transmitted very readily. These findings reinforce the concept of selectivity in transmission. The possible use of the young rat gut as a test for protein integrity is discussed. [ABSTRACT FROM AUTHOR]

The positions of the disulfide bridges in toxin Il of Androctonus australis Hector were investigated using proteolytic enzymes. The resulting peptides were separated by column and paper chromatography and high-voltage electrophoresis. Determination of the amino acid compositions of the cystinecontaining peptides or their oxidized derivatives and, when necessary, dansyl Edman degradation allowed to locate the disulfide bonds in the toxin. The four disulfide bridges were found to link the half-cystine residues number 12 and 63, 16 and 36, 22 and 46, 26 and 48. These positions are probably the same in all scorpion neurotoxins. [ABSTRACT FROM AUTHOR]

Tryptophan synthase was purified from Saccharomyces cerevisiae with the aid of affinity chromatography up to a specific activity of 525 units/g protein. Electrophoresis on polyacrylamide gel showed one main protein component. Gel filtration on Sephadex G-150 indicates an average molecluar weight of 143 000. Dissociation with dodecylsulfate followed by dodecylsulfate-acrylamide gel electrophoresis leads to the conclusion that the enzyme is probably composed of four subunits of equal size. The Km-values with respect to its substrates indoleglycerol phosphate, indole and L-serine were estimated. L-Serine was shown to increase the Km-value for indoleglycerol phosphate about 7-fold. Several indole analogues inhibit the tryptophan synthase reaction (B) (i.e. indole + serine → tryptophan); indoleacrylic acid is the most effective. The pH-optimum of tryptophan synthase is around 6.9 to 7.0. Sulfhydryl modification by 5,5'-dithiobis(2-nitrobenzoic acid) and p-chloromercuriphenylsulfonic acid results in a large loss of tryptophan synthase activity, which cannot be prevented by the substrates L-serine and indole. The tryptophan synthase inactivating system from yeast affects the catalysis of both reactions (A) (i.e. indoleglycerol phosphate → indole + glyceraldehyde 3-phosphate) and (B).

1. A two-dimensional gel electrophoresis procedure employing a combination of isoelectric focusing and dodecylsulfate elcctrophoresis has been used to analyse the components of 32P-labelled nonhistone protein fractions obtained by the chromatography of salt-urea dissociated chromatins on hydroxyapatite. 2. In this way the nonhistone proteins eluted from hydroxyapatite by 0.05 M phosphate (fraction H2) have been found to consist of a heterogeneous mixture of components of a molecular weight range of 15000 to 200000 and to have isoelcctric points between pH 4.5 and 9. The components of the fraction eluted from hydroxyapatite by 0.2 M phosphate (fraction H3) appeared to consist of a smaller group of proteins with a molecular weight range similar to that of the H2 proteins but whose isoelectric points lay between pH 2 and 6. Both fractions consisted of a mixture of phoshorylated and nonphosphorylated protein species. 3. Comparison of the components of H2 and H3 protein fractions by this electrophoretic procedure showed that many of the phosphorylated and nonphosphorylated proteins were common to mouse liver, kidney and brain chromatins. Only a few species were found to be tissue specific. 4. It was found that chromatography on QAE-Sephadex did not follow the same separation pattern as that obtained by isoelectric focusing, suggesting that the fractionation on this ion- exchange material is not entirely dependent on the overall charge of the polypeptide. 5. Preparation of individual nonhistone protein species has been attempted using this chromatographic procedure in conjunction with gel filtration in guanidine hydrochloride. [ABSTRACT FROM AUTHOR]

Mouse histocompatibility antigens were solubilized from lymphocyte membranes by limited papain degradation. Spleens from Balb/c mice (H-2d), enlarged by administration of lymphoma cells, were used for the membrane preparations. The solubilized protein components were purified by ion-exchange chromatography, gel filtration and discontinuous polyacrylamide-gel electrophoresis. A further characterization was achieved in a two-dimensional protein mapping system using disc-electrophoresis and isotachophoresis in the first and second dimension, respectively. The purification was monitored for alloantigens H-2.4(D) and H-3.21(K) (H-2D and H-2K represent two regions of the H-2 system). On Sephadex G-100 partially purified H-2-alloantigen chromatographed in a region of Mr = 35500. The pI of these substances showed a maximum at pH 5.5 and 5.3 for H-2.4 and at 5.2 for H-2.31. Free SH- and dithio-groups were determined with 5,5′-dithiobis(2-nitrobenzoic acid). 1.56 μmol SH/μmol alloantigenic material was found, but no SS-bond could be detected after alkaline cleavage. This suggests the absence of covalently linked protein subunits in papain-solubilized molecules bearing single private specificites. This was confirmed after reduction and alkylation in 4 M urea: 30-50% of the alloantigenic activity was retained and shown, in polyacrylamide-gel electrophoresis, to migrate in the original region of activity (RBPB 0.29 and 0.33 for H-2.4; about 0.33 for H-2.31, BPB = bromophenol blue). After reductive alkylation gel filtration resulted in a further purification of the alloantigenic material. Highly purified substances showed a diffuse staining pattern and a broad serological profile after electrophoresis. We assume this heterogenity to be a genuine property of H-2 antigens. Structural and genetic implications of these findings are discussed. [ABSTRACT FROM AUTHOR]

The serum proteins of the grey squirrel have been examined quantitatively by fluid agar electrophoresis and free boundary electrophoresis, and qualitatively by the combined techniques of Porath zone electrophoresis, starch gel electrophoresis, immunoelectrophoresis, and Sephadex chromatography. At least seventeen proteins, differing antigenically, can be distinguished. Unlike other mammalian sera, squirrel serum is relatively rich in pre-albumin components, of which there are two. The fastest of these is a lipoprotein. Of the many proteins classed as α-2 globulins, two are macroglobulins. [ABSTRACT FROM AUTHOR]

Antiserum to a fraction of mouse β globulin isolated by electrophoresis and column chromatography was found receive by immunoflouresence with renal basement membrane of glomeruli and tubules, and with basement membrane and connective tissue in other organs. This method for staining renal basement membrane was applied to the study of renal lesions produced in mice by streptolysin S. In lesions characterized by early changes of acute tubular necrosis a marked decrease in ability to stain tubular basement membrane was observed. Reapperance of staining property in basement membrane was linked to regeneration of diseased tubules. Repeated injections of streptolysin S produced alterations in staining also of glomerular basement membrane [ABSTRACT FROM AUTHOR]

The electrophoretic patterns of six sera from rabbits immunized by two or more courses of intravenous injections of killed pneumococci type III showed multiple peaks in the γ-globulin region. Such sera contained large amounts of anti-body (up to 85 per cent of the total γ globulin) against the capsular polysaccharide. One serum contained a cryoglobulin, which contained almost as great a proportion of specific antibody as did the remaining γ globulin. The electrophoretic patterns and antibody contents were similar in the water-soluble and water-insoluble fractions of γ globulin. The sedimentation constant and diffusion coefficient of a water-soluble fraction of γ globulin, containing 85 per cent specific antibody, were measured. The values, at 0.4 per cent protein concentration, were S20.w=6.97 × 10-13 and D20.w= 4.16x10-7 cm.² sec.-1, corresponding to molecular weight 159,000. The antibody-containing globulin from one serum was separated by zone electrophoresis into three fractions with different electrophoretic mobilities. These contained 53–71 per cent of antibody precipitable by type III pneumococcus capsular polysaccharide. Only doubtfully, significant differences were found in respect of amino-acid composition, hexose and hexosamine contents, or antigenic characteristics. A method was devised for detecting small amounts of antibody against capsular polysaccharide by means of red cells sensitized with culture filtrates of capsulated pneumococci. The antibody was also fractionated by chromatography on anion-exchange cellulose, and numerous fractions with antibody activity were obtained. It was shown by labelling the γ globulin with 131xI that similar fractionation occurred both in the presence and absence of other serum components. All the chromatographic fractions of γ globulin were found to contain approximately similar proportions of antibody. By electrophoresis in starch gel the fractions were found to differ from one another and to be heterogeneous. The implications are discussed of the finding that antibody against type III pncumococcus capsular polysaccharide can occur over the entire range of γ-globulin molecules. [ABSTRACT FROM AUTHOR]

Human allergic serum has been fractionated by: Chromatography on diethyl amino ethyl cellulose columns. Ultracentrifugation in buffered sucrose gradients. Passive transfer tests with the fractions showed skin sensitizing activity to horse dandruff allergen to be associated with an electrophoretic gammax­globulin component possessing a 7S sedimentation constant. The difficulties encountered in the use of the chromatographic procedure for obtaining potent reagin preparations are discussed. [ABSTRACT FROM AUTHOR]

An inhibitor from Pinus radiata was separated using paper chromatography from an acidic ether fraction of a stem tissue extract. Using electrophoresis the inhibitory activity was resolved into two parts. One part remained at the origin. The second part behaved similarly to ABA, in electrophoresis and was investigated further. The inhibitor has similar properties to ABA in electrophoresis; TLC using a number of solvent systems; UV fluorescence spectra: UV absorption; ORD spectra and gas chromatography. Final proof of the identity of the natural inhibitor as ABA was obtained by gas chromatography-mass spectrometry. [ABSTRACT FROM AUTHOR]

Radioactive leucine was incorporated by Neurospora crassa mitochondria in vivo in the presence of cycloheximide. When the membrane protein of these mitochondria was chromatographically separated on oleyl polymethacrylic acid resin, a number of fractions were obtained which differ with respect to their contents of radioactivity and cytochromes. The highest specific radioactivity was found in the fraction containing cytochrome aa3. This fraction proved to be a pure and enzymatically active cytochrome oxidase. Its ratio of absorbance at, 280 nm (ox)/ 443 nm (red.) was 2.1. By means of sodium dodecylsuffate gel-electrophoresis, this enzyme was separated into five polypeptides with molecular weights of 30000, 20000, 13000, 10000, and 8000. Only the polypeptide with the molecular weight 20000 displayed a high specific radioactivity. [ABSTRACT FROM AUTHOR]

A new method is described for the isolation of the subunits of porcine luteinizing hormone which have not been characterized before. By chromatography on SE-Sephadex C-25 in 8 M urea, the two subunits LHα and β were obtained in good yield and without apparent cross contamination. The physicochemical and immunological properties of these subunits were studied. Unlike the bovine or ovine LHβ subunits described earlier, porcine LHβ subunit does not contain lysine. Porcine LHα subunit is electrophoretically heterogeneous and two components represented by two homogeneous electrophoretical zones were isolated and characterized. The amino acid composition of these components is very similar; they differ, however, slightly in peptide maps of their tryptic digests. Whole LHα subunit was submitted to specific cleavage at methionine residues by cyanogen bromide and a homogeneous peptide not containing homoserine was isolated. The latter represents most probably the C-terminal fragment of LHα subunit. Its partial amino-acid sequence and composition is: Gly-Asn-Ala-Arg-Val-Glu-(His3,Lys,CM-Cys3-4,Asp,Thr2,Ser,Glu,Tyr2)-Ser. The fragment contains 34% of sugar (by weight). In view of the similarity in peptide maps and the unambiguous sequence described above, the primary structure of the different components of LHα subunit must be very similar. [ABSTRACT FROM AUTHOR]

Extracts of mycelium of Mucor rouxii have been shown to contain two forms of pyruvate kinase named Type I and II. They can be separated by DEAE-cellulose chromatography and by electrophoresis in polyacrylamide gel. Extracts from ungerminated sporangiospores or yeast-like cells contained only the Type I form. Pyruvate kinase Type II appears during aerobic germination of spores or during conversion of yeast-like cells to mycelium. Both pyruvate kinases are similar in theft molecular weight, pH range of activity, Km with respect to substrates and their response to activators (Mn++ and fructose 1,6-diphosphate). [ABSTRACT FROM AUTHOR]

A simple procedure for the isolation of C&macr1;-Inactivator from fresh human ACD plasma is described consisting of the following fractionation steps : DEAE chromatography, ammonium sulfate precipitation, Sephadex G-150 gel filtration and zone electrophoresis. A 250-fold concentration was achieved in good agreement with and immunologically determined C&1macr;-Inactivator concentration of 25 mg/100 ml serum. C&1macr;-Inactivator is a glycoprotein containing 35% carbohydrates; it migrates with the &alpha2;-globulins at pti 8.6 and in the PS-1 zone at pH 4.4. The isoelectric point is between 2.7-2.8. It had s20,w of 3.67 and a molecular weight of 104000 according sedimentation equilibrium patterns. C&1macr;-Inactivator could not be dissoziated in subunits even not by reduction with 2-mercaptoethanol and subsequent alkylation with iodoacetamide, 1mg C&1macr;-Inactivator neutralizes 17 C&1macr;-Inactivator units respectively 5 Remmert and Cohen plasmin units. Only weak affinities for trypsin and chymotrypsin were found. [ABSTRACT FROM AUTHOR]

The purification of eleven neurotoxins from the venom of three scorpions (Androctonus australis Hector, Buthus occitanus tunetanus and Leiurus quinquestriatus quinquestreatus) has been performed by Sephadex G-50 filtration (with and without recycling) and equilibrium chromatography on Amberlite CG-50, CM-Sephadex C-50 and DEAE-Sephadex A-50. All the chromatographic steps were carried out in ammonium acetate buffers. Purity of the neurotoxins was assessed by amino acid analysis and zone electrophoresis. All have a molecular weight of about 7000 daltons and do not contain methionine. As shown by amino acid composition and chain length scorpion neurotoxins show a high degree of homology. [ABSTRACT FROM AUTHOR]

1. β-Methylcrotonyl-CoA-carboxylase was purified 120-fold from an Achromobacter species. When the ceils were grown on isovaleric acid, the enzyme was formed mainly during exponential growth. The enzyme can be labeled by addition of radioactive biotin to growing cells. A former procedure of purification was improved by using adsorption to calcium phosphate gel and chromatography on Sephadex G-200. Enzyme homogeneous by both sedimentation and Tiselius electrophoresis was thus obtained in a yield of 40-70 % and was crystallized in a form resembling crystalline propionyl-CoA-carboxylase. 2. The molecular weight of the enzyme as determined by sedimentation velocity is 760000 daltons. The biotin content of 1,27 μmoles/g indicates 4 moles of biotin are bound to 1 mole of protein as is also the case for propionyl-CoA-carboxylase and pyruvate carboxylase. 3. Glutamic and aspartic acid comprise 23% of the amino acids in the enzyme. Extrapolation of electrophoretic mobility as a function of pH indicates the isoelcctric point of the enzyme is in the vicinity of pH 3.5. Such a value would mean that most of the carboxyl groups of the acidic residues are free. 4. The usual methods of preparations for electron microscopy, even with preceding fixation steps, cause degradation of the enzyme since only particles of about 1/4 of the expected size could be seen. However, ultracentrifugation did not indicate any dissociation of the enzyme into subunits. [ABSTRACT FROM AUTHOR]

No myoglobin was detectable in extracts from human uterus and taenia coli muscle by reaction with antibody against purified human skeletal muscle myoglobin. With Sephadex gel chromatography and starch gel electrophoresis no protein corresponding to this myoglobin was found in human smooth muscle extracts. The immunological procedure employed would have detected a concentration of skeletal muscle myoglobin as low as 0.001 mg/g muscle wet weight. [ABSTRACT FROM AUTHOR]

In order to determine the primary structure of the bovine β-caseins, the A2 variant was first cleaved with trypsin and cyanogen bromide (CNBr). The tryptic hydrolyzate was separated by column chromatography on Dowex-50. After additional purifications, 13 peptides numbered Ti to T13 were isolated. The 14th tryptic peptide, T14, not eluted from the column, was directly obtained from the hydrolyzate by preparative paper electrophoresis. Amino-acid analyses were carried out on all these peptides. Peptide T1 contain 2 Arginyl residues, one of which is NH2-terminal. This peptide represents the NH2-terminal end of the β-casein. Its composition is identical to that reposed by Peterson et al. in 1958 [1] for a phosphopeptide isolated from the β-casein. Peptide T11 contains 2 Lysyl residues, one of which is NH2terminal. The COOH-terminal peptide was identified with peptide T4, devoid of basic aminoacids. The 14 tryptic peptides account for all the residues of the β-casein A2 when compared with the already published amino-acid analyses of the whole protein [2, 3]. Several other peptides, originating from incomplete or non-specific cleavages, were also obtained. Similarly, 7 peptides accounting for the 6 methionyl residues of the protein were obtained from the same variant of β-casein after cleavage with cyanogen bromide. Six of these peptides were separated on Sephadex G-50. The seventh peptide was obtained by chromatography on Dowex-50 of the whole CNBr-digest. After additional purifications, the ammo-acid compositions of the 7 pure peptides were determined. Peptide CN1 contains peptide T1. It represents the NH2terminal end of β-casein. The COOH-terminal end of β-casein was identified with peptide CN7. As in the case of the tryptic peptides, the 7 CNBr-peptides account for all of the amino-acid residues of β-casein A2. β-casein A2 has 208 amino-acid residues. Its molecular weight is very close to 24 000. [ABSTRACT FROM AUTHOR]

The ℵ-chains were prepared by chromatography and rechromatography of pig S-sulfoimmunoglobulin on Sephadex G-100 and SE-Sephadex, and characterized by starch-gel electrophoresis, amino acid analysis, molecular weight (25 000 ± 2500) and N-terminal amino add (alanine). From the tryptic digest of the ℵ-chains, the N-terminal tetracosapeptide was isolated and its amino acid sequence determined as Multiples equation(s) cannot be represented by ASCII text. These results provide evidence of the similarity between pig immunoglobulin ℵ-chains and the human and mouse type K Bence-Jones proteins. [ABSTRACT FROM AUTHOR]

This paper is the first one of a series devoted to the primary structure of the major protein of cow's milk, αs1-casein, a single-chain phosphoprotein, formerly reposed to have arginine as an NH2-termimal, and Leu-TrpOH as COOH-terminal residues. ryptic digestion of maleyl αs1-casein (genetic variant B), in theory bruited to arginyl bonds, yields eight peptidic fragments, Tm1 to Tm8, which were fractionated by column chromatography and, in some cases, more thoroughly purified by preparative paper electrophoresis and/or chromatography. The ammo acid composition and the phosphate content of these fragments were determined. The fragments Tm3 and Tm8 arise from a partial non specific cleavage of Tm5. Thus, six fragments only—2, 4, 5, 6 and 7—arise from the specific cleavage of the αs1-casein chain at arginyl bonds, a result in accordance with the reported number of six arginyl residues in the chain, one being NH2-terminal. The fragment Tm7, with two arginyl residues, and Tm2 devoid of arginine appear to rcpresent respectively the NH2- and COOH-terminal parts of the αs1-casein chain. These peptidic fragments—except Tm4 which is devoid of lysine—were further digested by trypsin at lysyl bonds, after eliminating the blocking maleyl groups. The resulting peptides were purified by the same methods as mentioned above, and the composition of these tryptic peptides was established. As a control, the tryptic peptides of αs1-casein were simultaneously purified by the same methods from a hydrolysate of the protein which had not been treated with maleic anhydride. In summary, this first step of our work gives: (a) the composition of ail the bovine αs1-casein tryptic peptides; (b) partial information on the location of these peptides in the protein chain: (c) confirmation that the molecular weight of the bovine αs1-casein monomer is approximately 23600. [ABSTRACT FROM AUTHOR]

The ethanolic extract of 8-week-old parsley plants was chromatographed on Dowex-1×2 with a concave gradient using the buffer system of Hurlbert. After further purification on carboncelite columns, paper chromatography and high-voltage electrophoresis, 120 μmoles of a homogeneous UDP­sugar fraction were obtained. The sugars present in this fraction were identified after acid or enzymatic hydrolysis (Crotalus adamanteus venom, acid phosphatase) by various chemical and enzymatic tests. A modified Dische test which is specific for apiose and a quantitative deterruination of D­xylose with D­glucose—oxidase were developed. According to the analytical investigations the UDP­sugar fraction had the following composition (μmol): UDP-D-glucose (84), UDP-D-galactose (27), UDP-D-xylose (4), UDP-L-arabinose (2), UDP­fructose (0.42), UDP-L-rhamnose (2.4), and UDP­apiose (0.18). The presence of UDP­apiose in parsley strongly corroborates the proposed biosynthetic pathway for the formation of D-apiose via DDP-D-glucuronic acid. [ABSTRACT FROM AUTHOR]

An extracellular proteolytic enzyme from the culture medium of Penicillium notatum, obtained as a dry, tannin-precipitated powder from a commercial source, has been isolated. The purification procedures used include extraction of the crude proteinase with buffer from the commercial product, precipitation with ammonium sulphate, chromatography on DEAE­Sephadex A-25, gel filtration on Sephadex G-75, followed by ion-exchange chromatography on SE-Sephadex C-50, and finally zone electrophoresis on a cellulose column. Sufficient evidence is presented to show the purity of the isolated proteinase. Arguments for and against the presence of two distinct proteolytic enzymes from the same source are also presented. [ABSTRACT FROM AUTHOR]

Alkaline degradation of fusigen, a sideramine from fungi, yields the known monohydroxamic acid fusarinine. L-Ornithine and cis-5-hydroxy-3-methylpentenoic-2-acid occur in fusigen in equal amounts, and ornithine is the only amino acid. Amino group(s) with pK 7,1, but no free carboxyl group can be found in fusigen. The calculated equivalent weight is 280, which again points to fusarinine as a structural subunit. By acetylation of fusigen three products are obtained, which can be separated by electrophoresis or chromatography. The titration data of the partially acetylated fusigen and the molecular weight estimation by vapour pressure osmometry of the desferriform of the fully acetylated fusigen show that fusigen is a trimeric fusarinine. These data together with those obtained from IR- and NMR-absorption spectra lead to the proposed structure: three fusarinine molecules are esterified head-to-tail to build a 36-membered ring. The quantitative estimation of all hydroxamic acids in the culture fluid of Fusarium cubense from the 2nd to the 9th day of fermentation and structural studies on some of these compounds revealed the spontaneous degradation of fusigen by ring opening and sequential split-off of fusarinine units. An analogous degradation pathway starts from N-acetyl-fusigen. The Δ2-anhydromevalonic lactone, found in the cultures of several fungi, seems to stem from the degradation of fusarinine. The total yield of Δ2-anhydromevalonic lactone can be increased severalfold by treatment of the culture fluid with hydrochloric acid prior to extraction. [ABSTRACT FROM AUTHOR]

A new and efficient method for preparation of pure yeast phosphofructokinase is described, leading rapidly to an enzyme with minimum proteolytic alterations. Essential is an affinity chromatography step on the reactive dye Cibacron blue F3G-A® which has been covalently bound to Sephadex G-100. The enzyme prepared by this method has a significantly higher sedimentation constant (20.5 S) than those forms of yeast phosphofructokinase purified by procedures previously described (17.8 S) and is composed of two different kinds of subunits having molecular weights of 130000 and 96000, respectively. By gel filtration various enzyme fractions have been obtained, containing either mainly subunits of the 130000 or of the 96000 type, respectively. Samples of phosphofructokinase which have been prepared by the original and by the new method were compared by means of analytical gel chromatography and dodecylsulphate elcetrophoresis. In the course of the preparation procedure described previously, the enzyme is evidently proteolytically converted to the 570000 molecule by degradation of the subunits having 130000 molecular weight to those of 96000. [ABSTRACT FROM AUTHOR]

1. A simple and mild procedure is described for the isolation of equine growth hormone from frozen pituitary glands. it involves water extractions of the glands at pH 7.2 and 9,5, fractionation by ammonium sulfate precipitation and gel filtrations on a Sephadex G-100 column. The yield is 1.7 mg growth hormone per gram of fresh glands with a biological specific activity of 1.6 USP units/mg. 2. The protein obtained is homogeneous judged by disc electrophoresis, ultracentrifugation, gel electrofocusing, gel filtration and end-group analyses 3. A weight-average molecular weight of 20 200 was determined by sedimentation equilibrium analysis. Comparative values were found by gel electrophoresis and exclusion chromatography. Its Stokes radius and frictional ratio were 2.25 nm and 1 21, respectively. 4. The amino acid composition of equine growth hormone shows considerable analogy with those of bovine, ovine and porcine growth hormones. [ABSTRACT FROM AUTHOR]

The purification of a phosphodiesterase from Bothrops atrox venom by chromatography on phosphocellulose and affinity chromatography with O-(4-nitrophenyl)-O'-phenyl-thiophosphate ester coupled to activated Sepharose is described. Phosphatases are removed by chromatography on hydroxyapatite. The enzyme is a single-chain protein with a molecular weight of approx 130000 as judged by dodecylsulfate-gel electrophoresis and ultracentrifugation It has a specific activity of 3.3 μmol bis(4-nitrophenyl)phosphate hydrolyzed min-1 mg-1 at 24 °C. [ABSTRACT FROM AUTHOR]

1. Pork trypsin has been separated into several active forms by chromatography on sulpho-ethyl-Sephadex. 2 Two of these forms have been characterised by end-group determinations as a single chain form (the β-form) and a form (the α-form) with a single internal split in its peptide chain between a lysine and a serine residue. 3 The two peptide chains of the α-form have been separated by gel electrophoresis in the presence of sodium dodecylsulphate under reducing conditions and their molecular weights appear to be approximately 11000 and 13000 4. At a substrate concentration of 0.56 mM the β-form is 25% more active than the s-form against α-N-benzoyl-DL-argmtne-p-nitroanilide. [ABSTRACT FROM AUTHOR]

For the elucidation of amino acid sequence around the reactive site of soybean trypsin inhibitor (Kunitz), fragments A and B were digested with trypsin, and the resulting peptides were separated by ion-exchange chromatography on Dowex 50X2 or by gel filtration on Bio-Gel P-4. Further purification of the peptides was carried out by gel filtration on Sephadex G-25 or by high-voltage paper electrophoresis at pH 3.6 and 6.5. Nine peptides were obtained in pure form from fragment A and three peptides from fragment B, and their amino acid sequences were determined by the direct Edman method and by carboxy-peptidase digestion technique. Overlapping peptides necessary for the alignment of the tryptie peptides from fragments A and B were obtained from a chymotryptic hydrolysate of fragment AB by gel filtration on Bio-Gel P-4, and their ammo acid compositions and sequence analyses of some peptides made it possible to establish the amino acid sequence of an amino-terminal region of the inhibitor consisting of AB amino acid residues. The reactive site (Arg63-Ile64) of the inhibitor to trypsin was involved in this region. [ABSTRACT FROM AUTHOR]

The oxygenation of hemoglobin is under the control of the regulatory function of organic phosphates. The one in mammals corresponds to 2,3-bisphosphoglyccrate but in birds and turtles appears to be inositol hexakisphosphate. The latter component decreases the oxygen affinity of the two chicken hemoglobin compounds (the minor and the major) and the lone pigeon hemoglobin component. The Bohr effects have also been determined for the two hemoglobin samples. As has already been observed by electrophoresis and by chromatography, pigeon hemoglobin seems to behave more like that of the major chicken component by disclosing analogous log P50 values, i.e. the partial pressure of oxygen corresponding to a 50% load of the hemoglobin. [ABSTRACT FROM AUTHOR]

Tyrosinase was dissolved from the melanosome fraction of Harding-Passey mouse melanoma and purified further by Sephadex G-100 gel filtration and DEAE-cellulose column chromatography. The specific activity of the purified preparation was 763 times as high as that of the original melanosome. Tyrosinase thus isolated showed only a single activity in both the electrophoresis of a polyacrylamide gel and a cellulose acetate. The Km value is the same as those of the original melanosome and the smooth-surfaced-membrane. The relationship between particle bound tyrosinase and solubilized tyrosinase is discussed in this paper. [ABSTRACT FROM AUTHOR]

This article discusses the characterization of fountain pen inks by porous glass chromatography and electrophoresis. Identification of fountain pen inks and writing fluids has long been a subject of considerable interest to the examiner of questioned documents. In order to accurately identify the various ink formulations that are commercially available, many techniques using a variety of analytical procedures have been developed. Of these, perhaps the most accepted method in current usage is that of paper chromatography. This separation method allows the various ink components, many of which are colored dye substances, to be separated into integral bands or zones that distribute themselves in a manner characteristic of the original combined formulation. In an effort to overcome many of the inherent difficulties associated with paper as a chromatographic or electrophoretic medium, it was conceived that porous glass might offer properties which would permit such separations under a wider range of conditions. In addition, the final separations would be in a medium which was itself optically transparent. This unique glass was obtained and found to be quite acceptable for these applications.

From the lipopolysaccharide of the gram-negative bacterium Rhodopseudomonas capsulata (Athiorhodaceae) a lipophilic sugar was isolated by chromatographic procedures and characterized by mass spectrometry as belonging to the group of 3-O-methyl-6-deoxy-hexoses. Demethylation showed that the parental sugar had the same properties in borate electrophoresis as rhamnose. Comparison with an authentic sample of 3-O-methyl-rhamnose in gas liquid chromatography, paper chromatography and borate electrophoresis showed that the sugar under examination is 3-O-methylrhamnose (acofriose). Investigation of its optical rotation indicates that the sugar has the L-configuration. L-Acofriose (3-O-methyl-L-rhamnose) has not hitherto been found in lipopolysaccharides of gram-negative bacteria. [ABSTRACT FROM AUTHOR]