Trichinella spiralis: Proteins and antigens isolated from a large-particle fraction derived from the muscle larva

Proteins and antigens derived from a large-particle fraction of muscle larvae of Trichinella spiralis (i.e., the S₃ fraction) were characterized in terms of their molecular weights, isoelectric points, carbohydrate contents, electrophoretic mobilities, antigenicity, and their ability to induce protection in mice. Gel filtration on Sephacryl S-200 yielded 5 major peaks of material while electrophoresis in polyacrylamide gel with sodium dodecyl sulfate revealed a minimum of 28 proteins ranging in MW from 11,000 to 200,000. Analytical isoelectric focusing on acrylamide gel yielded 37 bands of protein, while the periodic acid-Schiff reaction performed on a similar gel revealed 22 glycoproteins. Most proteins were within a pI range of 4.0–7.0, while all of the glycoproteins had pI ranging from 4.0 to 6.5. Immunoelectrophoresis of the S₃ fraction using hyperimmune rabbit serum demonstrated a minimum of 19 precipitin arcs, while crossed immunoelectrophoresis yielded 16 peaks. These determinations were made on several batches of material isolated in the same fashion and gave the same results. Preparative isoelectric focusing yielded 30 fractions. These fractions were assayed for the presence of antigens, then pooled and tested for their ability to induce protection in mice against an oral challenge infection. Fused rocket immunoelectrophoresis of all 30 fractions revealed the presence of a minimum of 18 antigens with pI ranging from 4.0 to 9.0. The pooled fractions (i.e., 1–9; 10–20; 21–30) all protected mice against oral challenge infection, while fraction 5 (pI = 4.3) protected best.     

Structural studies on a carbohydrate chain isolated from the lipopolysaccharide of Shigella boydii type 8

The lipopolysaccharide isolated from the cells of Shigella boydii type 8 bacteria gave precipitin bands against homologous antisera on Ouchterlony plates, whereas the carbohydrate-containing fractions obtained from it did not. One of the fractions was obtained in major proportion and contained 23.5% of sugars. A structure was assigned to the carbohydrate chain in this material by using the results of methylation, periodate oxidation, and deamination studies.     

Multiple zeins from maize endosperms characterized by reversed-phase high performance liquid chromatography

The major storage proteins of maize (Zea mays L.) endosperm are located in protein bodies, and may be separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) into two major classes and four minor classes of polypeptides. The two major classes (commonly known as zeins) have been separated previously into a large number of components by isoelectric focusing (IEF). Reversed-phase high performance liquid chromatography (HPLC) further separated the major classes into additional components, and gave distinctive peaks for each minor zein class. Some IEF bands produced two or more HPLC fractions, while some HPLC fractions produced two or more IEF bands. Apparently identical IEF bands from different inbreds may appear in different fractions after HPLC. Thus the total number of zeins revealed by separations based on apparent size (SDS-PAGE), net charge (IEF), and hydrophobicity (HPLC) is very large. Different laboratories have developed diverse nomenclatures which cause much confusion. A key is presented to provide a flexible and expandable nomenclature for this complex group of proteins.     

Analysis of Biomphalaria glabrata (Gastopoda) hemolymph by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, high-performance liquid chromatography, and immunoblotting

Cell-free hemolymph (serum) of the gastropod mollusc Biomphalaria glabrata was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoreis (SDS-PAGE), high-performance liquid chromatography (HPLC), and immunoblotting. In SDS-PAGE gels, hemoglobin (Hb; apparent molecular weight (aMW) = 160 kDa) was found to be the dominant protein. There were also many subtending polypeptides in the 31,000 to 116,000 aMW range. In order to deplete B. glabrata serum of Hb it was ultracentrifuged by a standard procedure. The supernatant (Hb depleted) and pellet (Hb enriched) were then subjected to SDS-PAGE and HPLC. The polypeptide profile of the Hb-enriched fraction was virtually indistinguishable from whole serum whereas few major proteins were observed in the Hb-depleted fraction. Only by subjecting a large sample to SDS-PAGE followed by the very sensitive silver-staining procedure were several, faintly staining polypeptides observed in the Hb-depleted fraction in the aMW range of 10 to 116 kDa. Similarly, when the Hb-depleted fraction was subjected to HPLC, virtually no peaks were observed. In comparison, several peaks were discriminated from 9 to 12.5 min during chromatography with Hb producing a sharp spike at 13 min. When serum was separated by HPLC and the various fractions were subjected to SDS-PAGE, nearly all samples gave a polypeptide profile similar to whole serum. Rabbits were next used to raise antibodies to whole B. glabrata serum (anti-serum) and the 160-kDa polypeptide (anti-Hb). Rabbit antisera was then tested against whole snail serum and the Hb-depleted and enriched fractions in immunoblot assays. Both antisera gave similar results with reactivity against whole blood and the Hb-enriched fraction being virtually identical. In comparison, both anti-Hb and anti-serum reacted only with the 160-kDa polypeptide as well as two bands at approximately 55 kDa when tested against the Hb-depleted fraction. When the blots were counterstained, no other protein bands were visualized, indicating that each antisera was recognizing all of the proteins present. When the antibodies were tested against serum fractions separated by HPLC, nearly all fractions reacted in a manner similar to whole serum. No other polypeptides were observed when these blots were counterstained. From these experiments, it appears that Hb and Hb subunits comprise the majority of the serum proteins in B. glabrata.     

Identification of the B1 and B2 subunits of human placental laminin and rat parietal-yolk-sac laminin using antisera specific for murine laminin-beta-galactosidase fusion proteins.

Antisera raised against fusion proteins consisting of murine laminin B1 and B2 subunit sequences fused to the C-terminus of Escherichia coli beta-galactosidase were tested for their subunit specificity on Western blots of deglycosylated murine Engelbreth-Holm-Swarm (EHS) laminin. The antisera raised against B2 subunit sequences (anti-XLB2.1 and anti-XLB2.2) bound only to the EHS laminin B2 subunit. One of the antisera raised against B1 subunit sequences (anti-XLB1.2) was specific for the B1 subunit, whereas two others (anti-XLB1.1 and anti-XLB1.3) cross-reacted with the EHS laminin B2 subunit. Gold-labelled heparin-albumin was shown to bind specifically to the A subunit of deglycosylated EHS laminin on Western blots. These reagents were used to identify the homologous subunits in rat parietal-yolk-sac laminin and human placental laminin. The anti-(fusion protein) antisera identified the B1 and B2 subunits of the rat laminin, and these were similar in size to the murine EHS B subunits. Human placental laminin gave bands of 400, 340, 230, 190 and 180 kDa on reducing SDS/PAGE. The anti-(fusion protein) antisera identified the 230 and 190 kDa bands as the B1 and B2 subunits respectively. Gold-labelled heparin-albumin bound to the 400, 340 and 190 kDa bands of human placental laminin and so did not unambiguously identify a single A subunit. The human placental laminin may contain a mixture of isoforms, with alternative subunits substituting for the A subunit.     

Isolation of Fasciola hepatica genus-specific antigens

Santiago de Weil N., Hillyer G. V. and Pacheco E. 1984. Isolation of Fasciola hepatica genus-specific antigens. International Journal for Parasitology14: 197–206. The Fasciola hepatica antigens which induce antibody formation in acute fascioliasis were isolated by acid elution after reacting an F. hepatica tegument antigen extract with a CNBr-Sepharose 4B column coupled with IgG obtained from the serum of rabbits infected with fascioliasis for 6–10 weeks. These isolated antigens were further separated by gel filtration using a column packed with Sephacryl S-200. In this manner three major peaks were obtained. The best serologic antigens were found in peak 2 which had a mol. wt range of 14,000–43,000. This peak contains genus-specific F. hepatica antigens which are highly reactive with fascioliasis serum. These antigens do not cross-react with either Schistosoma mansoni or with bovine serum albumin by gel diffusion. Monitoring by ELISA and gel diffusion with heterologous and homologous antisera showed that as purification by antibody affinity chromatography proceeded, cross reactivity with S. mansoni was eliminated. The rabbit antiserum obtained against peak 2, when tested by immunoelectrophoresis with a crude F. hepatica extract shows one main band identical to the main band observed with serum from acutely infected rabbits. Up to two other minor bands can be detected using concentrated homologous antisera. Fractions obtained from preparative iso-electric focusing of the F. hepatica tegument extract were reacted with sera from rabbits with acute fascioliasis. Two main bands were observed in immunodiffusion with antigens eluting in a pH range of 7.4–8.7. When these fractions were monitored with anti peak 2 antisera, two precipitin bands appeared with antigens eluting in a pH range of 7.4–7.9. The F. hepatica genus-specific antigen pool was applied to ELISA to evaluate its ability to detect antibody in a primary F. hepatica infection in rabbits. A rise in absorbance values could be detected by 2 weeks of infection, reached high levels by 6 weeks and remained high through 28 weeks of infection.     

Application of the Laurell immunoelectrophoresis technique to the study of serological relationships between granulosis viruses

The Laurell technique of two-dimensional immunoelectrophoresis was used to distinguish between isolates of granulosis virus (GV) from Plodia interpunctella (GV strains A and B), Ephestia cautella, Spodoptera littoralis (GV strain 65), Pieris brassicae, and Cydia pomonella. Granules, alkali-soluble proteins, and virus particles of P. interpunctella GV strain A and granules of P. interpunctella GV strain B were used as sources of antigens. They were reacted with the immunoglobulins of antisera prepared against whole granules of each strain of virus. Peaks of precipitation were most clearly defined when antigens were pretreated with 0.1 m Na₂CO₃, 2% Triton X, and succinic anhydride, Granules and alkali-soluble proteins of P. interpunctella GV strain A treated in this way exhibited at least one peak of precipitation when reacted with each of the antisera studied. Four peaks were observed in both the homologous reaction and in the heterologous reaction with antiserum prepared against granules of P. interpunctella GV strain B. Four different peaks were present in the homologous reaction between immunoglobulins and virus particles of P. interpunctella GV strain A. Two peaks were present in the heterologous reaction with antiserum prepared against granules of P. interpunctella GV strain B and one in that with the antiserum prepared against granules of S. littoralis GV strain 65.     

Crossed-immunoelectrophoretic analyses of Trypanosoma cruzi epimastigote, metacyclic, and bloodstream forms

Sonicated suspensions of epimastigote, metacyclic, or bloodstream forms of Trypanosoma cruzi were emulsified in Freund's complete adjuvant. Rabbits immunized with epimastigotes or metacyclics received five intramuscular (i.m.) injections of 1 x 10(9) sonicated trypanosomes at weekly intervals. Immunization with bloodstream forms included three i.m. injections of 5 x 10(7) and six injections of 2 x 10(8) sonicated trypanosomes. Selected antisera from these rabbits were employed in crossed immunoelectrophoretic studies against the homologous or heterologous extracts of sonicated trypanosomes. Extracts of epimastigote, metacyclic, and trypomastigotes produced 31, 29, and 11 precipitin peaks respectively against the homologous rabbit antisera. Tandem, crossed-immunoelectrophoresis of these extracts against antiepimastigote or antimetacyclic sera revealed that epimastigotes or metacyclics may each have at least four antigens that did not appear to be shared by the other, whereas each of these forms may have at least eight or nine antigens that were not detected with extracts from trypomastigotes. Cross-absorptions of antiepimastigote or antimetacyclic sera with live trypanosomes caused marked reductions in the numbers of precipitin peaks formed against the homologous extracts, but cross-absorptions with sonicated suspensions of epimastigotes or metacyclics showed that epimastigotes or metacyclics each have at least two antigens that were not detected in extracts of the other. Differentiation appeared to be accompanied by antigenic change. More antigens appear to be shared by epimastigotes and metacyclic forms than by trypomastigotes and epimastigotes or metacyclics.     

A modification of the unlabeled antibody enzyme method using heterologous antisera for the light microscopic and ultrastructural localization of insulin, glucagon and growth hormone.

The requirement of using homologous antisera (primary antiserum and peroxidase-antiperoxidase (PAP) complex raised in the same species) in the unlabeled antibody enzyme method has been investigated at the light and electron microscopic level using the localization of insulin, glucagon and growth hormone as model systems. Optimum immunocytochemical staining for all three antigens was observed when sheep or goat antirabbit gamma-globulin (S-ARgammaG or G-ARgammaG) were used to couple rabbit peroxidase-antiperoxidase complex with either guinea pig antisera to insulin (GP-AIS) or glucagon (GP-AGS), or monkey antisera to rat growth hormone (M-ARGH). The cross-reactivity between S-ARgammaG or G-ARgammaG and immunoglobulins in these primary antisera were substantiated by immunoelectrophoresis and radioimmunoassay. S-ARgammaG was shown to produce precipitation arcs with GP-AIS and M-ARGH that were similar to those seen when the latter were reacted with rabbit antiguinea pig gamma-globulin antiserum and goat antimonkey gamma-globulin antiserum, respectively. Radioimmunoassay results revealed that immunoprecipitation of 6-10% as compared to homologous antisera controls yielded excellent staining localization when S-ARgammaG was used for immunocytochemistry. Thus, heterologous antisera (primary antiserum and PAP complex raised in different species) may be used in the unlabeled antibody enzyme method as long as the coupling antiserum shows cross-reactivity with immunoglobulins of the primary antiserum and the PAP complex.     

Polymorphic glutamate dehydrogenase in lilac vitroplants as revealed by combined preparative IEF and native PAGE: Effect of ammonium deprivation, darkness and atmospheric CO2 enrichment upon isomerization

The activity and polymorphism of glutamate dehydrogenase (GDH) were studied in basal callus of lilac ( Syringa vulgaris L.) vitroplants. Native PAGE alone revealed seven bands staggered at regular intervals. Preparative liquid-vein IEF allowed the separation of six to ten GDH fractions with charges ranging between 5.18 and 7.08. Analysis of these GDH fractions in native PAGE indicated that up to seven GDH bands can be detected for each fraction. This suggests the existence of seven isoforms of the enzyme with subunits presenting different isoelectric points. Dark- and ammonium-controlled forms were found to be the more acidic and faster migrating ones in native PAGE. The results support for the first time that atmospheric CO₂ enrichment increases GDH activity dramatically and modifies isomerization of the enzyme.     

Fractionation of polyclonal antibody by isoelectric focusing--differences in cross-reactivity and affinity of rabbit clonotype anti-human thyrotropin antibody

Immunoglobulin G (IgG) fractions prepared from three different batches of rabbit antihuman thyrotropin (hTSH) antisera were fractionated by agarose isoelectric focusing (IEF) in the pH ranges 3 to 10 and 5 to 8. Staining of protein in agarose gel after IEF showed that polyclonal IgG separated into more than 20 protein bands with isoelectric points (pIs) ranging from 6 to 9. The clonotype antibodies to hTSH were recovered from the fractions and subjected to radioimmunoassay for determination of the binding-affinity for hTSH and the cross-reactivity with human chorionic gonadotropin (hCG). The affinity constants of the antibodies recovered ranged from 6.4 X 10(9) M-1 to 3.1 X 10(10) M-1, and the cross-reactivities of the clonotype antibodies differed greatly. A good correlation was observed between the pIs of antibody molecules and their cross-reactivities: antibodies with higher pIs bound hCG more strongly than those with lower pIs. The correlation coefficients between the pIs and cross-reactivities were 0.83, 0.84, and 0.87 in three batches of antibody.     

Preparative isoelectric focusing of human serum very low-density and low-density lipoproteins.

Ten percent glycerol prevented the usual precipitation of human serum very low-density lipoproteins (VLDL) and low-density lipoproteins (LDL) at their isoelectric points during their preparative isoelectric focusing (IEF), IEF separated VLDL and LDL into two major fractions. The observed optical density peaks are not artifacts caused by binding of Ampholines to VLDL or LDL since no radioactivity accumulated in the fractions containing VLDL or LDL during IEF in the presence of [¹⁴C]Ampholine, and gel filtration completely separated the lipoproteins from [¹⁴C]Ampholine. These results suggest that IEF may separate subspecies of VLDL and LDL under suitable experimental conditions.     

Electrophoretic and immunologic characterization of proteins of merozoites of Eimeria acervulina, E. maxima, E. necatrix, and E. tenella.

Merozoites of Eimeria acervulina, Eimeria maxima, Eimeria necatrix, and Eimeria tenella were compared by gel electrophoresis, western-blotting with chicken antiserum, indirect fluorescent antibody reactions, and antiserum neutralization. Merozoites from the 4 species had dissimilar patterns of proteins and antigens in soluble and membrane fractions. Coomassie blue staining of SDS-PAGE gels revealed 16-22 protein bands depending on the species of merozoite but only 3 bands per species in the membrane fractions. Homologous and heterologous antisera recognized 5-12 soluble fraction bands and 3-7 membrane fraction bands on immunoperoxidase-stained western blots, depending on the species. When antisera from infected chickens were used in an indirect fluorescent antibody reaction, the merozoites of E. tenella and E. necatrix had a strong reaction with homologous and heterologous antisera. Merozoites of E. acervulina and E. maxima reacted with homologous antisera but had a weak or no reaction with heterologous antisera. Chicken antiserum against E. tenella had no effect on the viability of E. tenella merozoites when they were inoculated into chicken embryos.     

The similarity of antigenic proteins of<Emphasis Type="Italic">Fusarium nivale</Emphasis> (Fr.) Ces isolates

The degree of similarity among dissolvable in water proteins obtained from 10Fusarium nivale isolates was studied. Tandem crossed Immunoelectrophoresis method was applied. Two immunological antisera: anti-F. nivale 4 and anti-F. nivale 15 were used in the investigation. Their homologous reactions resulted in 13 and 12 precipitation bands, respectively. The results allow to divide the isolates into three groups, according to their protein composition.     

Studies on the effect of 3,4-dehydroproline on collagen metabolism in carbon tetrachloride-induced hepatic fibrosis.

The lectin from Euonymus europeus seeds was purified by adsorption onto insoluble polyleucyl hog A + H blood group substance and subsequent elution with lactose. The isolated lectin formed three lines in immunoelectrophoresis against rabbit antisera to the crude seed extract and showed three components on electrophoresis in acrylamide gel at pH 9.4. In analytical isoelectric focusing the purified lectin had six closely spaced bands with pI from 4.3 to 4.7. It sedimented as two peaks: a big symmetrical peak with s_20,w⁰ of 7.8 and another small, diffuse moving peak. The intrinsic viscosity was 0.057 dl/g and the M_r calculated from the sedimentation coefficients, intrinsic viscosity, and V? of 0.71 was about 166,000. In sodium dodecyl sulfate, it gives subunits of M_r 17,000 and 35,000; 20% of the 35,000 subunit resists reduction by dithiothreitol in 7 m guanidine-HCl. The Euonymus lectin is a glycoprotein containing 4.8% d-galactose, 2.9% d-glucose, and 2.8% N-acetyl-d-glucosamine. The purified lectin precipitated well with B and H blood group substances and with the P1 fraction of blood group B substance but not with A₁ substances. It precipitated poorly with Le^a and Le^b and precursor I blood group substances. Inhibition of precipitation with milk and blood group oligosaccharides showed the lectin to be most specific for blood group B oligosaccharides having the structure: dGalα1 → 3[lFucα1 → 2]dGalβ1 → 3 or 4dGlcNAcβ→. It is also inhibited by blood group H oligosaccharides but to a lesser degree. For 50% inhibition of precipitation, 3.5, 850, and 290,000 nmol of B and H oligosaccharides and lactose, respectively are required. The B and H specificities are an intrinsic property of a single lectin site since absorption and elution from an H immunoadsorbent gave material with B as well as H specificity. Millipore-filtered crude extracts of Euonymus europeus preserved with 0.02% sodium azide are stable in the refrigerator for many months and can be used for quantitative precipitin and for quantitative inhibition assays, results being the same as with purified lectin.     

The effect of ampholytes on ferritin isoelectric focussing patterns

Ferritin was subjected to isoelectric focussing (IEF) on agarose gels containing different commercial carrier ampholytes. In two gels protein staining revealed banded patterns which differed from one another, while a third gel yielded zones rather than discrete bands, indicating that the bands may be artefacts.The differences between banded patterns were studied by isolating bands from an IEF gel and refocussing these on gels containing either the original ampholyte or a different ampholyte preparation. Striking differences were noted.Chromatofocussing of ferritin resulted in the elution of broad peaks between the same pH limits as indicated by IEF patterns.     

Schistosoma japonicum: disc electrophoretic protein patterns of the Japanese, Philippine, and Formosan strains

Soluble proteins of the Japanese, Philippine, and Formosan strains of Schistosoma japonicum were separated by disc electrophoresis using polyacrylamide gel columns. Differences between strains and sexes were investigated on the basis of R_f values of the bands, location of prominent peaks, quantitative comparisons of major bands, and overall densitometric profiles. With male extract, 29, 28, and 29, distinct bands were resolved for the Japanese, Philippine, and Formosan strains, respectively. Female extracts gave 31, 26, and 25 distinct bands for the Japanese, Philippine, and Formosan strains, respectively. Both qualitative and quantitative differences were found among the three strains and between sexes. The closest relationship of densitometric profile was between the Japanese and Formosan strains.     

Further characterization of the beta-glycoprotein of the rabbit uterus

beta-Glycoprotein was isolated from preimplantation uterine secretions of the rabbit by gel- and ion-exchange chromatography. Two fractions, called DF1 and DF2, were analyzed by isoelectric focusing (IEF) and sodium-dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) in combination with Western blotting and immunoelectrophoresis. DF1 displayed 21 bands with isoelectric points of pH 5.2-7.6, and DF2 15 bands of pH 4.2-5.7. SDS-PAGE yielded up to 14 bands with major components at molecular weights of 63,000 and 135,000 respectively. Two-dimensional gel electrophoresis of DF2 in combination with Western blotting revealed five groups of proteins of equal molecular weights but with different isoelectric points, indicating immunological identities. Glycosidase activities in uterine secretions before and after implantation were studied and compared with those of the blastocyst fluids. alpha-L-Fucosidase co-eluted with DF1, and beta-N-acetylglycosaminidase was distributed in DF1 and DF2. Both enzymes were localized on isoelectric focusing gels, and N-acetylglucosaminidase was also demonstrated in an immunoprecipitate of DF1.     

Some serological properties ofActinobacillus pleuropneumoniae strains of serotypes 1 through 5

Rabbits were hyperimmunized with live, formalin-killed, and heat-treated antigen preparations of the reference strains of serotypes 1 through 5 ofActinobacillus pleuropneumoniae in order to study the antibody response to both soluble and particulate antigens. The antibody response was studied by means of precipitation, agglutination, coagglutination, indirect hemagglutination, and complement fixation tests.Serotyping ofA. pleuropneumoniae strains was done by ring precipitation (RP) and coagglutination (CoA) tests with unheated and heated cell-saline extract as antigens and rabbit hyperimmune sera produced against either live cultures or formalin-killed whole-cell suspensions. The results showed that live cultures provoked more cross-reactive antibodies in rabbits, thus making the antisera unsuitable for use in serotyping by the RP test when unheated wholecell saline extract was used as antigen. Rabbit hyperimmune serum produced against formalinkilled bacterial suspension gave serotype-specific reactions in the RP test. Boiled or autoclaved cell-saline extracts gave serotype-specific reactions in the RP test even when rabbit anti-livecell sera were used. Serotype-specific reactions were obtained in the CoA test in both rabbit anti-live or anti-formalin-killed cell sera with either unheated or heated bacterial cell suspensions as antigens.Live and formalin-killed whole-cell suspensions as well as their saline extracts provoked a high antibody response in rabbits. Heating the cell suspension at 100°C for 1 h caused a significant reduction in their immunogenic potency, whereas autoclaving (121°C) of the cell suspension for 1 h almost completely destroyed their serotype-specific immunogenic properties, since the antibody response was either absent or very poor and not type-specific. However, neither boiling nor autoclaving of the cell suspensions caused significant reduction in their ability to react with preformed antibodies. Phenol-water-extracted antigens gave the highest degree of serotype specificity in the complement fixation test.     

麻蝇幼虫肠道蛋白酶BGP的分离纯化及性质

棕尾别麻蝇幼虫肠液经ＳＤＳ－ＰＡＧＥ后,Ｘ光片显影,呈现两条蛋白酶活性带．ＩＥＦ后,两条蛋白酶活性带的等电点分别为ｐＨ７．７和６．８．麻蝇幼虫肠液经５５％～７５％硫酸铵沉淀,以及连续两次制备等电聚焦,分离纯化出等电点约为ｐＨ７．７,分子量约为３５ｋＤ的蛋白酶ＢＧＰ．该酶能分解酪蛋白和类胰蛋白酶专一底物Ｂｚ－Ｐｈｅ－Ｖａｌ－ＡｒｇＮＡ,不能分解弹性蛋白酶专一底物ｅｌａｓｔｉｎ－ＣｏｎｇｏＲｅｄ和类胰凝乳蛋白酶专一底物Ｓｕｃ（Ａｌａ）２Ｐｒｏ－ＰｈｅＮＡ．ＳＢＢＩ,Ｌｅｕｐｅｐｔｉｎ和ＰＭＳＦ能强烈抑制其活性．专一底物和抑制剂的结果表明,ＢＧＰ是一种类胰蛋白酶．其最适反应温度为５０℃,最适作用ｐＨ为８．５．不耐高温,５０℃保温３０ｍｉｎ活性急剧下降．Ｈｇ２＋,Ｚｎ２＋和Ｃｕ２＋能抑制酶活性．Ｃａ２＋,Ｍｇ２＋对酶无激活作用,ＥＤＴＡ无抑制作用．