Electrophoretic analysis of pancreatic proteases and zymogen-activating factors in the mouse

Mouse pancreatic proteases were analyzed by one- and two-dimensional electrophoresis. Active proteases that existed in the luminal fluid were separated into at least eight bands in 8% polyacrylamide gel. Pancreatic proteases activated by intestinal extract were separated into at least seven bands. The mobilities of these bands were exactly the same as those of proteases in the luminal fluid except for those of the most cathodal band. Two kinds of trypsin (Try-I group and Try-II) and one kind of chymotrypsin (Chy-I) were determined by specific and nonspecific protease staining. Try-I group and Try-II were derived from different trypsinogens (Try G-I group and Try G-II), whereas Chy-I was derived from a single chymotrypsinogen (Chy G). Although Try G-II was activated by both intestinal extract and by bovine trypsin, Try G-I group activated only by intestinal extract. Intestinal-activating factors were analyzed by two-dimensional electrophoresis. Mouse enterokinase (enteropeptidase EC 3.4.4.8), which can activate bovine trypsinogen, had a slow mobility. In the intestine of the mouse there are several activating factors in addition to enterokinase. Although it is unclear what intestinal-activating factors can activate Chy G, there is a factor that can convert chymotrypsinogen into chymotrypsin directly. These data suggest that intestinal-activating factors play an important role in the activating mechanisms of mouse pancreatic zymogens.     

Studies on the Molecular Weights of Esterase and Peroxidase Isozymes of Maize

The molecular weights of esterase and peroxidase isozymes of maize seedlings were directly determined by improved polyacrylamide gradient gel electrophoresis. The different isozyme bands developed in polyacrylamide slab gel electrophoresis (uniform gel) were identified in polyacrylamide gradient gel electrophoresis by means of isozyme variants. The molecular weights of esterase isozymes E1, E2, E3F, E3S, a, b, c, named according to isozyme patterns in uniform gel, are <20000, 35200, 33000, 38500, 29900, 28500, 34000 doltons respectively. The molecular weights of peroxidase isozymes PX4F and PX4S are 131000 and 149000 doltons respectively. According to the band location in uniform gel and in gradient gel, some biochemical properties of the isozyme bands and relationships between the isozyme bands were analyzed. The possible errors in the determination of smaller molecular weight isozymes are discussed.     

Catalytic properties and mode of action of endo-(1-->3)-beta-D-glucanase and beta-D-glucosidase from the marine mollusk Littorina kurila

A complex of the enzymes from the liver of the marine mollusk Littorina kurila that hydrolyzes laminaran was investigated. Two (1-->3)-beta-d-glucanases (G-I and G-II) were isolated. The molecular mass of G-I as estimated by gel-permeation chromatography and SDS-PAGE analysis was 32 and 40kDa, respectively. The G-II molecular mass according to SDS-PAGE analysis was about 200kDa. The pH optimum for both G-I and G-II was pH 5.4. The G-I had narrow substrate specificity and hydrolyzed only the (1-->3)-beta-d-glucosidic bonds in the mixed (1-->3),(1-->6)- and (1-->3),(1-->4)-beta-d-glucans down to glucose and glucooligosaccharides. This enzyme acted with retention of the anomeric configuration and catalyzed a transglycosylation reaction. G-I was classified as the glucan endo-(1-->3)-beta-d-glucosidase (EC 3.2.1.39). G-II exhibited both exo-glucanase and beta-d-glucoside activities. This enzyme released from the laminaran glucose as a single product, but retained the anomeric center configuration and possessed transglycosylation activity. The hydrolysis rate of glucooligosaccharides by G-I decreased with an increase of the substrate's degree of polymerization. In addition to (1-->3)-beta-d-glucanase activity, the enzyme had the ability to hydrolyze p-nitrophenyl beta-d-glucoside and beta-d-glucobioses: laminaribiose, gentiobiose, and cellobiose, with the rate ratio of 50:12:1. G-II may correspond to beta-d-glucoside glucohydrolase (EC 3.2.1.21).     

Purification of transferrin and albumin from mouse ascites fluid

Mouse ascites fluid, which is readily obtained when cell lines and hybridomas are maintained in host mice, is a convenient source of several plasma proteins. This paper describes procedures for the purification of albumin and transferrin from mouse ascites fluid. Mouse transferrin was prepared from a 50-75% ammonium sulfate fraction of mouse ascites fluid by CM- and DEAE-cellulose chromatography. Mouse albumin was obtained by the same purification route, but required an additional chromatography step on Cibacron Blue F3GA-agarose. Both proteins were shown to be homogeneous by polyacrylamide gel electrophoresis and immunoelectrophoresis. Characterization, which included a determination of amino acid composition, partial N-terminal sequence, molecular weight and extinction coefficient, correlated well with known values reported for human transferrin and albumin. The purified mouse proteins may be useful for biochemical studies, antibody preparation, and as growth factors for hybridomas or other mouse cell lines maintained in culture.     

Purification of Transferrin and Albumin from Mouse Ascites Fluid

Mouse ascites fluid, which is readily obtained when cell lines and hybridomas are maintained in host mice, is a convenient source of several plasma proteins. This paper describes procedures for the purification of albumin and transferrin from mouse ascites fluid. Mouse transferrin was prepared from a 50–75% ammonium sulfate fraction of mouse ascites fluid by CM- and DEAE-cellulose chromatography. Mouse albumin was obtained by the same purification route, but required an additional chromatography step on Cibacron Blue F3GA-agarose. Both proteins were shown to be homogeneous by polyacrylamide gel electrophoresis and Immunoelectrophoresis. Characterization, which included a determination of amino acid composition, partial N-terminal sequence, molecular weight and extinction coefficient, correlated well with known values reported for human transferrin and albumin. The purified mouse proteins may be useful for biochemical studies, antibody preparation, and as growth factors for hybridomas or other mouse cell lines maintained in culture.     

Basic isozymes of chymotrypsin-like esteroprotease from the mouse submandibular gland

Basic isozymes of chymotrypsin-like esteroprotease from mouse submandibular glands were purified 60-80-fold by a rather simple procedure consisting of CM-Sepharose CL6B chromatography and gel filtration on Sephadex G-100. The purified sample contained three major isozymes (A, B, C) and some minor ones. Their isoelectric points were between pH 10 and 11. The molecular weights of the main isozymes were estimated at 28000 by SDS-polyacrylamide gel electrophoresis. The acidic isozyme (A) separated into two polypeptide chains whose molecular weights were 21500 and 6500. Specific activities of these isozymes using Bz-Tyr-OEt as substrate were comparable to that of bovine pancreatic alpha-chymotrypsin, but they hydrolyzed casein 10 times slower than did alpha-chymotrypsin. The hydrolytic activities of these isozymes on Bz-Tyr-OEt were inhibited by diisopropylfluorophosphate, tosyl-L-phenylalanine chloromethyl ketone and chymostatin, but they were 400 times less sensitive to chymostatin than was alpha-chymotrypsin.     

Isolation and partial characterization of secreted mouse pituitary prolactin.

Prolactin secreted by mouse anterior pituitaries was purified by gel filtration on Sephadex G-100. Electrophoretic homogeneity of the purified hormone was demonstrated in several gel systems, and electrophoresis in the presence of sodium dodecyl sulfate indicated an apparent molecular weight of 21 000 +/- 2000. Mouse and ovine prolactin displayed parallel dose vs. response curves in radio-receptor binding studies, indicating that these two hormones compete for identical receptor sites on rabbit mammary membranes. Comparative peptide mapping studies carried out on tryptic digests of mouse and ovine prolactin suggested only partial homology between the two hormones. Internally labeled monomeric mouse prolactin was observed to undergo aggregation following storage at --20 degrees C for 2 months.     

Distribution and classification of acylphosphatase isozymes

Distributions of acylphosphatase isozymes among organs of several animal species were investigated. Organ extracts of pig and chicken were treated with isozyme-specific antibodies, subjected to electrophoresis on a polyacrylamide gel, then the gel was stained for acylphosphatase activity. Both animals showed three activity bands; one band was named common type isozyme because of its wide distribution in testis, muscle, brain, heart, spleen, kidney, liver, and erythrocyte, and the other two bands were named muscle type isozymes because of their localization in skeletal muscle. This classification was supported by selective and quantitative reactions of the isozymes to the isozyme-specific antibodies. Because the two bands of the muscle type have the same amino acid sequence and differ only in modifications on an -SH group, it is suggested that pig and chicken have only the two major types of acylphosphatase. This conclusion was supported by similar experiments on dog, human, rabbit, and pigeon.     

聚丙烯酰胺凝胶电泳配合荧光增白剂显色检测木霉几丁质酶同工酶谱

为提高木霉几丁质酶检测方法的准确性和灵敏度,建立一种快速检测几丁质酶同工酶的方法。采用活性凝胶电泳、变性凝胶电泳、原位显色凝胶电泳结合荧光增白剂（Calcofluor white M2R）显色从绿色木霉LTR-2发酵产物中检测几丁质酶同工酶。活性凝胶电泳在粗酶液浓缩5倍时显示两条活性谱带,变性凝胶电泳在浓缩10倍时显示一条活性谱带,原位显色凝胶电泳在浓缩20倍时显示两条不清晰的活性谱带,SDS-PAGE显示这两条活性谱带的分子量分别为65kDa和42kDa。结果表明活性聚丙烯酰胺凝胶电泳和Calcofluor white M2R显色相结合的方法在几丁质酶上样量为0.47U时具有较好的分辨能力,是检测木霉几丁质酶同工酶的有效的方法。     

Association study and expression analysis of CD9 as candidate gene for boar sperm quality and fertility traits

Cluster-of-differentiation antigen 9 (CD9) gene expressed in the male germ line stem cells is crucial for sperm-egg fusion, and was therefore selected as candidate gene for boar semen quality. The association of CD9 with boar sperm quality and fertility trait was analyzed using a total of 340 boars both from purebred Pietrain and Pietrain×Hampshire crosses. A single nucleotide polymorphism (g.358A>T) in intron 6 was significantly associated with sperm motility (MOT) (P<0.001), plasma droplet rate (PDR) (P<0.001) and abnormal spermatozoa rate (ASR) (P<0.01). Boars were divided into two groups with group 1 (G-I) boars having a higher SCON and SMOT, lower SVOL (sperm volume) and group 2 (G-II) having a lower SCON and SMOT, higher SVOL. The mRNA and protein expression levels were evaluated in reproductive, non-reproductive tissues and spermatozoa from G-I and G-II animals by using quantitative real-time PCR and western blotting. When both reproductive and non-reproductive tissues were examined, highest mRNA was expressed in prostate gland, then in the body of the epididymis, vas deferens and tail of the epididymis. In case of reproductive tissues, CD9 expression was higher in tissues and spermatozoa collected from G-I boars than those collected from G-II boars. The mRNA expression was significantly different (P<0.05) in body of epididymis from G-I and G-II boars. The CD9 protein expression results from western blot were coincided with the results of qRT-PCR. Moreover, CD9 protein localization in Leydig cells, Sertoli cells, epithelial cells and spermatozoa was remarkable which indicated the important role of CD9 in spermatogenesis process. By using mRNA and protein expression profiles, it could be shown that CD9 plays a crucial role during sperm development, especially within the epididymis where the maturation of the sperm, a key process for the sperm quality and motility takes place. These results will improve the understanding of the functions of the CD9 in spermatogenesis within the reproductive tracts and will shed light on CD9 as a candidate gene in the selection of good sperm quality boars.     

Phosphodiesterase-phosphomonoesterases from Fusarium moniliforme. VI. A modified method of purification and identification of isozymes.

Fusarium phosphodiesterase-phosphomonesterase was purified 1,630-fold with 19% yield from dried powder of the culture medium by a modified method consisting of seven steps. The purified preparation was shown to be devoid of inactive protein by disc electrophoresis. The preparation was homogeneous with respect to size as demonstrated by gel filtration, sodium dodecyl sulfate-polyacrylamide gel electrophoresis and ultracentrifugation. The molecular weights determined by gel filtration on Sephadex G-200 and by sodium dodecyl sulfate-polyacrylamide gel electrophoresis were 106,000 and 100,000, respectively. The sedimentation coefficient at infinite dilution was 5.71 S. Isoelectric focusing of the purified preparation showed the presence of at least four isozymes with isoelectric points of 6.6, 6.3, 6.2, and 5.9.     

玉米酯酶同工酶和过氧化物酶同工酶的分子量研究

本试验利用聚丙烯酰胺凝胶梯度电泳分步染色法直接对玉米苗期酯酶同工酶和过氧化物酶同工酶各酶带的分子量进行了比较测定。酯酶同工酶 E_1、E_2、E_3~F、E_3~S、a、b、c 各酶带的分子量分别为<20000,35200、33000、38500、29900、28500、34000道尔顿过氧化物酶同工酶 PX_4~F和 PX_4~S酶带的分子量分别为131000和149000道尔顿。根据酶带在均匀胶和梯度胶中的位置变化对各酶带的生化性质作了初步分析,发现 E_3~F和 E_3~S、PX_4~F 和 PX_4~S 在迁移率上的差异主要是分子量的差异。本文为同工酶的分子量测定提供了一个简便的方法。     

L-alpha-Hydroxyacid oxidase isozymes. Purification and molecular properties.

L-alpha-Hydroxyacid oxidase isozymes from rat liver (A isozyme) and kidney (B isozyme) have been isolated in a high state of purity with specific activities of 61 and 14.7 microkatals per gram protein respectively. The subunit molecular weights determined by sodium dodecylsulphate polyacrylamide gel electrophoresis were 40000 +/- 3000; the mouse A and B isozymes were also partially purified and their subunit molecular weights shown to be 37000.     

Mouse prolactin obtained by pituitary organ culture in a serum-free medium.

Mouse prolactin was purified by organ culture of pituitaries and electrophoresis of the medium. Mouse pituitaries were organ-cultured in 9-cm Petri dishes containing Waymouth's medium (MB 752/1) supplemented with penicillin (50 units/ml), streptomycin (100mug/ml), and bovine insulin (0.12 I.U./ml) for 8 days. Prolactin-rich culture medium was half-saturated with ammonium sulfate and centrifuged. The pellet was subjected to analytical disc electrophoresis (10% acrylamide). Gels were sectioned into 2-mm segments. Prolactin was eluted in 0.04M phosphate buffer (pH 7.2), dialyzed and lyophylized. Two hundred and forty ml medium in which 360 pituitaries were cultured yielded 29.3 mg lyophylized mouse prolactin. Although the preparation contained 2 other bands on acrylamide gel disc electrophoresis, a single precipitin line was seen in immunodiffusion and immunoelectrophoresis, showing the identity of their antigenicity. From these results, two other proteins in the preparation were suggested to be deamidated prolactin.     

Structural components of mouse mammary tumor virus. II. Isolation and purification of virion polypeptides.

Mouse mammary tumor virus (MMTV) glycoproteins and nonglycosylated polypeptides were purified by preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Primary amino groups were labeled with fluorescamine to enable visualization of MMTV polypeptides in the gels. Protein bands were sliced from the gels and eluted with 90 to 95% recovery. Eight MMTV polypeptides, including three of the major viral components as well as five minor proteins, were routinely obtained. Double diffusion assays and immunoelectrophoresis confirmed the retention of antigenicity identical to that of untreated MMTV virions. Antisera obtained from MMTV-free BALB/c mice immunized with these purified proteins reacted with the polypeptide immunogen as well as with detergent-disrupted MMTV virions from mouse milk or cell culture. Double diffusion assays using the specific mouse antisera failed to detect any cross-reactivity among the isolated polypeptides. A hemagglutination-inhibition assay demonstrated that the ability of MMTV virions to inhibit the hemagglutinating properties of influenza virus resides in the glycosylated polypeptides gp52, gp37.7, and gp33.     

Characterization of two endopolygalacturonase isozymes produced by Fusarium oxysporum f. sp. lycopersici.

Polygalacturonase (EC 3.2.1.15) produced by Fursarium oxysporum f. sp. lycopersici was purified by chromatography on DEAE-cellulose, CM-cellulose, and hydroxyapatite. The purified enzyme consisted of two electrophoretically distinct "isozymes", that behaved as charge isomers during electrophoresis in several different concentrations of polyacrylamide gel. The two isozymes had similar "endo" modes of action on polygalacturonic acid, as determined by comparison of viscosity reduction, reducing group release, and thin-layer chromatography of oligomeric hydrolysis products. Both isozymes hydrolzyed 5% of the substrate bonds in reaching 50% viscosity reduction. The amino acid compositions of the isozymes were similar and their molecular weights were about 37000 as determined by sedimentation equilibrium. Removal of large amounts of carbohydrate during purification did not affect heat stability of the enzymes. A large proportion of the remaining carbohydrate appeared to be covalently linked to the enzyme protein.     

Immunoaffinity purification of Schistosoma mansoni soluble egg antigens

Schistosoma mansoni egg antigens were purified from a heterogeneous mixture of soluble egg antigens (crude SEA) with an immunoaffinity column that consisted of the specific anti-SEA antibodies contained in 16-week S. mansoni-infected mouse serum bound to Sepharose 4B. On sodium dodecyl sulfate (SDS) gel electrophoresis, the purified antigen fraction yielded at least eight bands staining with Coomassie blue and at least five bands staining with Coomaisse blue and at least five bands reacting with periodic acid-Schiff (PAS). All of the proteins in the antigenic fraction appear to contain carbohydrate residues. Upon immunoelectrophoresis the antigen yielded four precipitin arcs. The antigenic fraction isolated by means of the immunoaffinity column was then compared to various fractions obtained from concanavalin A (Con A) chromatography of SEA. The results of Ouchterlony immunodiffusion and immunoelectrophoresis indicate that the antigenic fraction isolated by immunoaffinity purification of SEA contains the major antigens found in the fractions obtained from Con A chromatography of SEA. The results of SDS gel electrophoresis indicate that the major PAS-reacting bands of the antigenic fraction isolated by immunoaffinity purification are found in the 3rd peak (bound fraction) resulting from Con A chromatography of SEA, whereas the major Coomaisse blue-staining band in the isolated antigenic fraction is found in the 2nd peak (unbound fraction) from Con A chromatography of SEA.     

Immunological and biochemical properties of metallothioneins of golden hamster,mouse and rat

Summary Golden hamster, mouse and rat hepatic cadmium metallothioneins (MT) were purified by Sephadex G-75 gel filtration, DEAE-Sephadex A-25 chromatography and activated Thiol-Sepharose 4B affinity chromatography. Metallothioneins were separated by DEAE-Sephadex A-25 chromatography into two forms: MT-1 and MT-2. In mouse and golden hamster liver, MT-1 was the major form. The purified proteins were homogeneous as judged by polyacrylamide gel electrophoresis in the presence and absence of sodium dodecyl sulfate. In non-denaturing polyacrylamide gel electrophoresis, migration of mouse, rat and golden hamster hepatic metallothioneins were found to be different. Antibodies to mouse hepatic MT-1 was raised in rabbits. The antiserum cross reacted with mouse and hamster MT-1 and MT-2 giving a single precipitin band. Mouse, rat and hamster hepatic MTs are immunologically identical but electrophoretically different. The kidney and pancreatic MTs of rat and golden hamster were purified by Sephadex G-75 gel filtration. They were immunologically distinct. Pancreas MT formed a line of partial identity with hepatic MTs. Kidney MTs form two precipitin band one identical with the pancreatic form and another of complete identity with the hepatic MTs. This indicates the presence of tissue specific MTs.     

Purification of bovine and porcine enterokinase by affinity chromatography with immobilized kidney bean enterokinase inhibitor

A specific enterokinase inhibitor isolated from kidney bean (Phaseolus vulgaris) was immobilized on Affigel-10. Solubilized preparation of bovine and porcine enterokinases were bound to this matrix at pH 7.5 and the complex was dissociated by elution with l0 mM HCl, resulting in the isolation of the enzymes in homogeneous form as judged by gel chromatography on Sephadex G-200, and sodium dodecyl sulphate-polyacrylamide gel electrophoresis. However, human enterokinase could not be purified by this method in sufficient yield since it did not bind strongly to the insolubilized inhibitor.     

Phosphorylation of axonemal proteins in Chlamydomonas reinhardtii.

In order to determine whether microtubular proteins of flagellar axonemes were phosphorylated, cells of Chlamydomonas reinhardtii were grown in medium containing [32P]orthophosphate for several generations. Only one (alpha subunit) of the two tubulin polypeptides separated by Na dodecyl-SO4-polyacrylamide gel electrophoresis appeared labeled, as detected by autoradiography of the dried gel. 3H- and 32P-labeled alpha tubulin subunit purified by preparative Na dodecyl-SO4-polyacrylamide gel electrophoresis and Na dodecyl-SO4-hydroxyapatite chromatography contained about 0.2 mol of phosphate per mol of polypeptide. Upon partial acid hydrolysis, radioactivity could be accounted for as serine and threonine phosphate. By altering the conditions of the Na dodecyl-SO4-polyacrylamide gel electrophoresis is was possible to resolve the purified alpha-tubulin subunit into five or more components: a major band comprising approximately 65% of the total mass, not phosphorylated, and four or more minor bands comprising together 35% of the mass. Among the minor components at least two were phosphorylated.