ANALYSIS OF "NATIVE" CEREBROSPINAL FLUID BY THE POLYACRYLAMIDE DISC ELECTROPHORESIS TECHNIQUE

The polyacrylamide disc electrophoresis technique has been applied to the fractionation of ;native' cerebrospinal fluid. Evidence is presented to show that there is an alteration in the protein profile if the fluid is subjected to a concentration stage. A minimum of 22 distinct protein zones have been detected in fluids from patients without structural changes in the nervous system. The method has also been applied to pathological fluids and the differences are discussed.

[The effect of periodic stretching of the smooth-muscle cells on the expression in them of contractile-phenotype marker proteins]

Cyclic mechanical stretching of the rabbit aortic smooth muscle cells induced a serum-independent increase in the h-caldesmon expression. The expression was more obvious in the cells grown on laminin. The data obtained suggests that the cyclic stretching specifically activates a serum- and matrix-independent expression of h-caldesmon. The mechanical stimulation seems to contribute to the maintenance of the VSMC differentiated phenotype.

[Purification of acetylcholinesterase from human erythrocytes using metal-chelate affinity chromatography]

Acetylcholinesterase (AChE) was purified on columns with iminodiacetate Agarose charged with Cu2+, Zn2+, and Ni2+. The best results (a 14-fold purification and more than 30% activity yield) were obtained with Zn2+ used as a complex-forming metal. The preparation had a specific activity of approximately 7 U. Its purity was tested by polyacrylamide gel electrophoresis under denaturing conditions.

[Use of aerosol OT reverse micelles in heptane for purifying superoxide dismutase from erythrocytes]

Reversed micelles of Aerosol-OT (AOT) in heptane were used to purify superoxide dismutase (SOD) from bovine red blood cells. Effects of pH, temperature, concentrations of NaCl and protein in the aqueous phase, and the AOT to protein ratio on the extraction of the concomitant proteins from the aqueous into micellar phase were studied. The conditions were found that provided the extraction of concomitant proteins into micelles of AOT in heptane and left SOD in the aqueous phase. The SOD was electrophoretically pure; therefore, the need for its purification using chromatography was excluded.

Isolation and analysis of nephritic-producing immune complexes in Plasmodium berghei-infected mice

A nephritic condition was developed by infecting Swiss Webster albino mice with the malarial parasite Plasmodium berghei NK 65. These animals were tested for urinary protein and the presence of circulating immune complexes using reagent strips and a polyethylene glycol (PEG) precipitation assay. The circulating immune complexes were isolated from the sera using both affinity chromatography and PEG precipitation and from the kidney by acid elution. The isolated complexes were dissociated into their individual components and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The components of the complexes were transferred to nitrocellulose sheets and probed for the presence of malarial antigens using a rabbit anti-P berghei antisera. The overall humoral response to the malarial parasite was evaluated using a radial immunodiffusion assay. The present study confirmed that the malarial-infected animals not only developed the nephritic condition (as evident by the high levels of proteinuria) but also, as indicated by the PEG assay, have the presence of high levels of circulating immune complexes in their serum. The apparent absence in the SDS gels of any abnormal protein bands followed by the inability of the Western blot to reveal any malarial antigens provides some of the strongest evidence to date that these malarial proteins are not directly involved in the circulating immune complexes believed to be responsible for producing this nephritic condition.

Protective efficacy of cell-free-antigen of Actinobacillus pleuropneumoniae in mice

Cell-free-antigen (CFA) vaccines of strain Y-1 (serotype 1), G-4 (serotype 2) and E-3 (serotype 5) of Actinobacillus pleuropneumoniae (A. pleuropneumoniae) were prepared by emulsifying concentrated culture supernatant with oil-adjuvant. Mice immunized with the CFA vaccine had a high survival rate (90-100%) against challenge with the homologous strain. They also had cross-protective activity against challenge with the heterogeneous strains but their survival rate was low (20-50%). On the other hand, mice immunized with whole cell vaccine showed serotype specific protection and only a little cross protection. The protective antigens of the CFA were investigated. MAbs were produced by the standard method using spleen cells of mice immunized with CFA. MAbs to Apx I, II, III and capsular antigen of serotype 5 were obtained. Only MAbs to Apx I showed hemolysin neutralization activity among them. The protective effect of these MAbs against A. pleuropneumoniae infection were examined by passive immunization. Administration of Apx I MAb to mice extended survival time after challenge with serotype 5. The mice showed partial cross-protection against challenge with serotype 1. Survival rate was considerably low after the challenge infection. None of the mice given MAbs to Apx II or III were protected against challenge with serotype 5. The mice given MAb to capsular antigen of serotype 5 had a high survival rate (70%) against a challenge with a homologous serotype. Furthermore, mice given MAbs against Apx I and capsular antigen of serotype 5 were completely protected against a challenge with A. pleuropneumoniae serotype 5.(ABSTRACT TRUNCATED AT 250 WORDS)

Imaging electrophoretic gels with a scanning beam laser macroscope

A scanning beam laser macroscope has been developed which scans an area of 7.5 x 7.5 cm in 5 s. This new imaging system is examined as a potential tool for scanning electrophoretic gels. A specially-designed telecentric, f* theta laser scan lens is used in the instrument to achieve a linear scan and a flat focal plane. The laser scan lens focuses the incoming beam from a laser to a 10 microns spot inside the gel. A raster scan is performed across the gel and the signal is detected with a photomultiplier, forming a 512 x 512 digital image stored as a computer file. Silver-stained protein polyacrylamide gels have been imaged in transmission and double-transmission, while DNA agarose gels (stained with ethidium bromide) have been imaged in fluorescence with better than 25 pg sensitivity. The macroscope has the advantage that it is not tied to the electrophoresis system as are end-of-line scanners, and the scan is rapid, so that several gels can be scanned in a very short time.

The isolation and characterization of non-typeable Haemophilus influenzae from the sputum of adult cystic fibrosis patients

The role of non-typeable Haemophilus influenzae in cystic fibrosis (CF) remains unclear. We wanted, therefore, to determine the presence and characteristics of non-typeable H. influenzae in sputum samples from patients with CF. In order to do this, we have assessed sputum samples from 55 consecutive clinically stable patients seen routinely at an adult CF out-patient clinic. Quantitative bacterial culture was performed using a selective media containing cefsoludin, and isolates were characterized by biotyping and outer membrane protein profile analysis. In 17 (30%) of these samples, non-typeable H. influenzae was isolated and was present in similar viable numbers (mean 7.7 x 10(8) colony-forming units (cfu).mL-1; SEM 3.1) to Pseudomonas aeruginosa (mean 8 x 10(8) cfu.mL-1: SEM 2.4). All non-typeable H. influenzae isolates recovered were beta-lactamase negative and sensitive to a range of antibiotics. Several biotypes and outer membrane protein profiles were observed, with no apparent association between these two phenotypic characteristics. The study showed that large numbers of non-typeable H. influenzae are often present in sputum from adult patients with CF. Further longitudinal studies of outer-membrane protein profile analysis are required to determine the dynamics of non-typeable H. influenzae colonization in individual patients and the clinical significance.

Soluble CD14 from urine copurifies with a potent inducer of cytokines

Here we report that soluble CD14 isolated from the urine of nephrotic patients (uCD14) contains a potent cytokine inducing activity. CD14 derived from urine appeared to consist of two major polypeptides of about 54 and 48 kDa. In uCD14 isolated from three different nephrotic patients the cytokine-inducing activity appeared to co-migrate with the 48-kDa polypeptide which upon sequencing had the same N-terminal sequence as native CD14. Treatment of human monocytes and the human astrocytoma cell line U373 with uCD14 resulted in a strong secretion of tumor necrosis factor (TNF) and interleukin-6, respectively. The cytokine-inducing activity of the uCD14 preparations was unaffected by the absence of serum. This is in contrast to the activation of human monocytes and U373 cells by lipopolysaccharide (LPS) which is highly dependent on the presence of serum. The cytokine-inducing activity was not affected by LPS-binding protein (LBP) or polyclonal rabbit antibodies against LBP. The TNF-inducing activity of uCD14 was also heat labile in contrast to the cytokine-inducing activity of LPS, which was relatively heat resistant. The results suggest that CD14 may exist in at least two forms of which one is involved in cytokine induction.

Heterodimeric deoxynucleoside kinases of Lactobacillus acidophilus R-26: functional assignment of subunits using limited proteolysis controlled by end-product inhibitors

Heterodimeric quaternary structures for two enzyme complexes from Lactobacillus acidophilus R-26 exhibiting deoxycytidine kinase/deoxyadenosine kinase (I) and deoxyguanosine kinase/deoxyadenosine kinase(II) activities have been proven by the following steps: (1) separation of each complex into two components on SDS-PAGE at pH 6.6; (2) N-terminal amino acid sequencing of each component; (3) functional assignment of each component by differential limited proteolysis. The third step was facilitated by the finding that the binding of a specific end-product inhibitor dNTP, to each kinase active site makes the corresponding kinase subunit resistant to trypsin, while leaving the heterologous kinase subunit susceptible to proteolysis. Analysis on SDS-PAGE has revealed only two fragments (15.8 and 11.0 kDa) following proteolysis of dCyd kinase/dAdo kinase (I) with trypsin in the presence of dATP. This may indicate that the kinase polypeptide chain (27.2 kDa) not protected by dNTP is cut by trypsin at a single specific site, with concomitant loss of activity. Thus, this work presents a unique approach to the clarification of structure and function of enzymes composed of heterologous subunits.

A di-heme cytochrome c peroxidase from Nitrosomonas europaea catalytically active in both the oxidized and half-reduced states

A di-c-heme containing cytochrome (cytochrome c553 peroxidase) has been isolated from the chemoautotrophic bacterium Nitrosomonas europaea. Sequence analysis of the N terminus and the two heme-containing peptides generated by digestion of the enzyme with trypsin show 40% homology overall to sequences reported for the di-heme peroxidase from Pseudomonas aeruginosa (Rönnberg, M., Kalkkinen, N., and Ellfolk, N. (1989) FEBS Lett. 250, 175-178). At room temperature and pH 7.0, one heme is low spin with Em7 = +450 mV and the other is high spin with Em7 = -260 mV. EPR spectra show a mixture of high spin and low spin signals at cryogenic temperatures. Anionic ligands (CN-, N3-, F-, CNO-) bind so as to perturb the high spin heme when cytochrome c553 peroxidase is either fully oxidized (FeLS3+:FeHS3+) or half-reduced (FeLS2+:FeHS3+). The EPR signal of the high potential, low spin heme in fully oxidized enzyme is unperturbed by the presence of the ligands. Furthermore, each ligand results in similar characteristic EPR signals for either oxidation state of the peroxidase. Both the fully oxidized and half-reduced oxidation states of cytochrome c553 peroxidase are catalytically active as evidenced by the enzyme's ability to oxidize horse heart cytochrome c in the presence of H2O2, as well as by optical changes associated with the addition of H2O2 to the peroxidase. In the presence of stoichiometric amounts of H2O2, the half-reduced enzyme is rapidly oxidized and the fully oxidized enzyme shows a significant decrease in absorbance in the Soret region of the optical spectrum coupled with a lesser increase near 600-650 nm. These latter optical changes are similar to what is observed in the formation of a porphyrin cation radical. This suggests that this di-heme peroxidase may form a compound I intermediate analogous to that formed by horseradish peroxidase.

Absence of cooperativity for MgATP and verapamil effects on the ATPase activity of P-glycoprotein containing membrane vesicles

Purified membrane vesicles were prepared from Chinese Hamster lung fibroblasts expressing high amounts of P-glycoprotein (P-gp), which is responsible for the multidrug resistance. P-gp ATPase activity, characterized in the presence or absence of verapamil, had a Michaelian behavior for its MgATP dependence. Thus only one MgATP molecule should be sufficient for the catalytic cycle. With increasing verapamil concentrations, a bell-shape curve was observed for ATPase activity, with half-activation and -inhibition concentrations of 1.2 microM and 490 microM, respectively. No cooperativity for verapamil was detected. These results strongly suggest that P-gp functions as an active transporter, with a coupling stoichiometry of one MgATP molecule hydrolysed for one verapamil molecule transported.

Purification and characterization of maleylacetate reductase from Alcaligenes eutrophus JMP134(pJP4)

Maleylacetate reductase (EC 1.3.1.32) plays a major role in the degradation of chloroaromatic compounds by channeling maleylacetate and some of its substituted derivatives into the 3-oxoadipate pathway. The enzyme was purified to apparent homogeneity from an extract of 2,4-dichlorophenoxyacetate (2,4-D)-grown cells of Alcaligenes eutrophus JMP134. Maleylacetate reductase appears to be a dimer of two identical subunits of 35 kDa. The pI was determined to be at pH 5.4. There was no indication of a flavin prosthetic group. The enzyme was inactivated by p-chloromercuribenzoate but not by EDTA, 1,10-phenanthroline, or dithiothreitol. Maleylacetate and 2-chloromaleylacetate were converted with similar efficiencies (with NADH as cosubstrate, Km = 31 microM for each substrate and kcat = 8,785 and 7,280/min, respectively). NADH was preferred to NADPH as the cosubstrate. Upon reduction of 2-chloramaleylacetate by the purified enzyme, chloride was liberated and the resulting maleylacetate was further reduced by a second NADH. These results and the kinetic parameters suggest that the maleylacetate reductase is sufficient to channel the 2,4-D degradation intermediate 2-chloromaleylacetate into the 3-oxoadipate pathway. In a data base search the NH2-terminal sequence of maleylacetate reductase was found to be most similar to that of TfdF, a pJP4-encoded protein of as-yet-unknown function in 2,4-D degradation.

Relationship between content of hepatic glutathione S-transferases and the kinetics of indocyanine green elimination in various liver diseases

The glutathione (GSH) S-transferases are believed to have dual functions as hepatic detoxifying enzymes and intrahepatic binding proteins. Little is known about their alterations in human liver diseases. Therefore, we have studied the relationship between the enzyme activity and rose bengal (RB) binding in hepatic cytosol and plasma indocyanine green (ICG) kinetics in patients with various liver diseases. The enzyme activity was measured in samples of hepatic cytosol obtained from 52 patients. In addition, the content of cationic and neutral transferases was estimated in 17 biopsy samples by densitometry of Coomassie blue stained sodium dodecyl sulphate polyacrylamide gel electrophoretograms. RB binding studies also were performed on cytosol samples. ICG kinetic parameters were determined using the two-compartment open model in 17 patients who were given the dye (0.5 mg kg-1) intravenously. Correlations between the enzyme activity and liver function tests, content of the enzyme, RB binding and ICG kinetic parameters were evaluated. The following results were obtained. (1) The enzyme activities were high in alcoholic liver disease, fatty liver and Gilbert's syndrome, and low in cirrhosis. (2) The enzyme activities were positively correlated with serum cholinesterase activity, serum albumin level and hepaplastin test, and negatively correlated with ICG retention rate at 15 min. (3) The enzyme activity, its content and RB binding affinity of the cytosol were positively correlated with each other. (4) The enzyme activity was positively correlated with hepatic ICG distribution volume. These results are consistent with the role of the GSH S-transferases as ligandins in intracellular storage of dyes.

Purification of a capillary permeability-increasing enzyme-2 from the venom of Agkistrodon caliginosus (Kankoku-Mamushi)

A capillary permeability-increasing enzyme-2 was purified from the venom of A. caliginosus by ion-exchange chromatography and gel filtration on Sephadex G-100. By this procedure, 3.1 mg of purified enzyme was obtained from 4 g of the venom. The mol. wt of the purified enzyme was estimated to be approximately 44,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme hydrolyzed N-alpha-tosyl-L-arginine methylester with a specific activity of 56.5 units/mg of protein, and did not show any caseinolytic, clotting or bradykinin-releasing activity. When 13.9 micrograms of the enzyme was injected into the depilated skin on the back of a rabbit, capillary permeability was increased.

Tyrosine-rich acidic matrix protein (TRAMP) accelerates collagen fibril formation in vitro

Tyrosine-rich acidic matrix protein (TRAMP) is a recently discovered protein that co-purifies with porcine skin lysyl oxidase and is equivalent to the M(r) 22,000 extracellular matrix protein from bovine skin that co-purifies with dermatan sulfate proteoglycans (Cronshaw, A. D., MacBeath, J. R. E., Shackleton, D. R., Collins, J. F., Fothergill-Gilmore, L. A., and Hulmes, D. J. S. (1993) Matrix 13, 255-266; Neame, P. J., Choi, H. U., and Rosenberg, L. C. (1989) J. Biol. Chem. 264, 5474-5479). The effect of TRAMP on collagen fibril formation was studied in vitro by reconstitution of fibrils from lathyritic rat skin collagen I. Fibril formation was initiated by the warm start procedure, in which acidic collagen solutions and double strength neutral buffer, both preincubated separately at 34 degrees C, were mixed. When monitored by turbidimetry, TRAMP was found to accelerate collagen fibril formation. Acceleration occurred at sub-stoichiometric molar ratios of TRAMP collagen, and the presence of TRAMP stabilized the fibrils against low temperature dissociation. It was confirmed by centrifugation that the amount of fibrillar collagen formed in the presence of TRAMP was greater than in its absence. By SDS-polyacrylamide gel electrophoresis and scanning densitometry, binding of TRAMP to collagen was detected that approached saturation with a molar ratio of TRAMP to collagen of approximately 1:2. Fibrils formed in the presence of TRAMP were normal when observed by electron microscopy, although fibril diameters were smaller than the controls. TRAMP was found to partially reverse the inhibitory effects of urea and increased ionic strength on the kinetics of fibril formation, although inhibition by glucose was unaffected. TRAMP also accelerated the assembly of pepsin-treated collagen, where the non-helical, telopeptide regions were partially removed. Acceleration of collagen fibril formation by TRAMP is discussed in the light of the known effects of other extracellular matrix components on this process.

[The neurochemical correlates of plasticity]

Water-soluble proteins in the CNS of Helix pomatia were studied by the method of disk electrophoresis in polyacrylamide gel. The protein Rf 0.58 proved to be absent in young snails, while in adults its amount varied from 3% (naive snails) to 6-10% (trained animals) of the proteins separated by the method used. Incubation of the adults' ganglia in saline containing serotonin or NaF led to a significant elevation of the protein Rf 0.58 quantity. Neither serotonin nor NaF induced the protein Rf 0.58 in the young snails. We suggest the protein Rf 0.58 to be related to G-proteins. Late maturation of G-proteins might be one of the reasons of low behavioural plasticity in the young snails. Influence of acetylcholine on the protein synthesis in the identified "pool D" neurons was studied too. Protein fractions were identified, in which the intensity of labelling increased up to 400-500% of the control level. Acetylcholine is supposed to modulate the protein synthetizing system in these neurons.

Purification of a second kallikrein from bovine pancreas

Two kallikreins were identified in a homogenate of bovine pancreas in terms of their differential elution from an anion-exchange chromatography column. The kallikreins were quantified by their ability to release kinin from a partially purified preparation of bovine kininogen. The second kallikrein, designated kallikrein B, was purified by a three-step procedure following anion-exchange chromatography consisting of affinity chromatography on a benzamidine-agarose resin, gel filtration and hydrophobic interaction chromatography. An overall purification factor of 556-fold was achieved with a 58% recovery of enzymatic activity. The final material was shown to be homogeneous by a number of electrophoretic analyses. The relative molecular mass of pro-kallikrein B was found to be 26,700 by gel filtration and that of kallikrein B to be 26,000 by SDS gel electrophoresis. Gel isoelectric focusing revealed the presence of several isoenzymic forms ranging in isoelectric point from pH 4.05 to 4.35.

Induction of stress proteins in mouse peritoneal macrophages by oxidized low-density lipoprotein

The synthesis of 23-kDa and 34-kDa proteins in mouse peritoneal macrophages was enhanced when they were incubated with oxidatively modified low-density lipoprotein (LDL). This response required the oxidation of the lipid of the LDL, because native LDL had little effect and acetylated LDL enhanced the synthesis of 34-kDa protein only slightly. Since macrophages can bind and sequester oxidized LDL, they are subjected to an oxidative stress. The results suggest that the 34-kDa protein, which is identical with heme oxygenase, and the 23-kDa protein serve as stress protein that might afford protection against the oxidative stress.

Purification and analysis of a human sarcoma associated antigen

S1, a heterophile antigen present on human sarcoma cell lines in culture, has been previously defined by this laboratory [1,2]. This antigen is also present in guinea-pig kidney. Purification of the antigen to homogeneity has now been achieved by a combination of ammonium sulfate fractionation, DEAE-cellulose, sephadex, high pressure liquid chromotography and affinity chromotography. S1 is a monomeric protein of 70,000 Da, as indicated by the presence of a single band on SDS-PAGE. Amino acid analysis demonstrates the prevalence of glycine, lysine and glutamic acid. Aspartic acid was found to be the N-terminal residue with further sequence of glycine-valine-alanine-glutamic acid (gly-val-ala-glut).

The distribution of saliva and sucrose around the mouth during the use of chewing gum and the implications for the site-specificity of caries and calculus deposition

Over a 20-minute period, subjects expectorated 8 samples of whole saliva (EWS) while chewing gum. Flow rates were calculated, and sucrose was analyzed in these samples as well as in saliva collected on filter paper strips from different tooth surfaces. Salivary film velocity (SFV), based on a 0.1-mm-thick film, was estimated from the clearance half-times of KCl in agarose disks positioned in different regions of the mouth. Salivary flow rate peaked at 5.1 mL/min in the first min but fell to about 1.25 mL/min by the end of the 20 min of gum-chewing. In contrast, flow rate when subjects sucked sour lemon drops averaged about 5.3 mL/min throughout the 20-minute period. The mean salivary sucrose concentration during gum-chewing peaked in the second min at 384 mmol/L (13.1%) but had fallen to 14 mmol/L by the 15-20-minute time interval. The sucrose concentrations on the palatal surfaces of the upper incisors and the facial and lingual surfaces of the lower molars were not significantly different from that in EWS but were much lower on the facial surfaces of the upper incisors and molars, and on the lingual surfaces of the lower incisors. When flow was unstimulated, SFV was 0.8-1.0 mm/min on the facial surfaces of the upper incisors and lower molars but about 5-8 mm/min on the facial surfaces of the upper molars and on the lingual surfaces of the lower incisors and molars.(ABSTRACT TRUNCATED AT 250 WORDS)