Purification, and properties of a base non-specific acid ribonuclease from bullfrog (Rana catesbeiana)

An acid ribonuclease (RNase RCL2) was purified to homogeneity on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) from a homogenate of bullfrog liver (Rana catesbeiana). The apparent molecular weight estimated from SDS-PAGE was ca. 25kDa. The pH optimum of the RNase was 5.0. The RNase released mononucleotides from RNA in the order of 3'-UMP, 3'-GMP and 3'-AMP. The N-terminal amino acid sequence of RNase RCL2 was determined up to the 20th residue, and it was found to have a 5 residue sequence homology with that of oyster acid RNase [H. Watanabe et al. J. Biochem. (Tokyo), 114, 800 (1993)]. Thus, RNase RCL2 seems to be a member of the RNase T2 family RNases. This is the first evidence of the RNase T2 family RNase in amphibians.

Role of Lys108 in the enzymatic activity of RNase Rh from Rhizopus niveus

In order to elucidate on the mechanism of action of RNase Rh from Rhizopus niveus, we investigated the role of Lys108, which is conserved among the RNase T2 family RNases except for two cases. The RNase activities of Lys108 mutant RNases, RNase RNAP K108R and K108L, are about 33.5 and 3.1% of that of the wild type enzyme, respectively. The relative rates of cleavage of dinucleoside phosphates by these two mutant enzymes were comparable to those with RNA as a substrate. The kinetic parameters of RNases RNAP K108R and K108L towards XpGs (where X is one of A, G, U, and C) were measured. The data indicated that the Km values of the two mutant enzymes are similar to those of the wild-type enzyme. The rates of release of the four nucleotides from RNA by digestion with the mutant enzymes were in the order A > G > U > C, which is qualitatively the same as that of the wild-type enzyme. From these data, we concluded that the Lys108 residue participates in the catalytic process, but not in the binding, and the positive charge of Lys108 is indispensable for the catalytic process, that is, the positive charge of Lys108 may stabilize the pentacoordinated intermediate in the transition state as proposed in the case of Lys41 in RNase A, or may polarize the phosphate moiety of the substrate.

Purification and primary structure of a new guanylic acid specific ribonuclease from Pleurotus ostreatus

A guanine nucleotide-specific RNase (RNase Po1) was isolated from caps of the fruit bodies of Pleurotus ostreatus. RNase Po1 is most active towards RNA at pH 8.0. The effect of heating on the molar ellipticity at 210 nm of RNase Po1 showed that RNase Po1 is more stable than RNase T1. The primary structure of RNase Po1 was determined to be < ETGVRSCNCAGRSFTGTDVTNAIRSARAGGSGNYPHVYNNFEGFSFSCTPTFFEFPVFRGSVYSGGSPG ADRVIYD- QSGRFCACLTHTGAPSTNGFVECRF. It consisted of 101 amino acid residues, with a molecular weight of 10,760. RNase Po1 has relatively higher sequence homology with RNase T1 family RNase. It contains 6 half cystine residues. The locations of four of them are superimposable on those of RNase U1 and RNase U2. The amino acid residues forming the active site of RNase T1 were well conserved in this RNase. Therefore, RNase Po1 is a unique member of the RNase T1 family in respect of the location of one disulfide bridge, and its stability.

pH profile of kinetic constants of RNase Rh from Rhizopus niveus and its mutant enzymes towards UpU, and possible mechanisms of RNase Rh

In order to elucidate the mechanism of action of Rhizopus niveus RNase Rh, we investigated the pH profiles of the kinetic parameters of RNase RNAP Rh, a derivative of RNase Rh, and its mutant enzymes, i.e., RNase RNAP Rh H104F, RNase RNAP Rh E105Q, and RNase RNAP Rh D51N. Based on comparisons of their profiles we concluded that protonation of His104 is indispensable for the enzymatic activity and Glu105 accelerates the enzymatic activity, especially at acid pH centered at pH 3.5. Based on these data and the previous data on the chemical modification and enzymatic properties of other mutant enzymes, we propose the following as a possible mechanisms of RNase Rh action. (i) His109 participates in enzymatic action as a general base catalyst which removes the hydrogen of the 2'-OH of the ribose moiety. (ii) His46 participates in the reaction as a general acid catalyst which interacts with the 5'-oxygen atom of the scissile phosphodiester bond and becomes a proton donor to the departing nucleoside or nucleotide. (iii) His104 interacts with phosphate anion and its protonation is favorable for the enzymatic activity. (iv) Since the protonated form of Glu105 is more favorable for activity, we postulate two possible roles for Glu105: (a) its stabilizes the intermediate, and (b) it interacts with the oxygen atom of P = O and polarizes the phosphorus atom.

Purification, some properties, and primary structure of a base non-specific ribonuclease from oyster (Crussdstrea grigus)

A ribonuclease (RNase Oy) was purified to homogeneity on SDS-PAGE from the homogenate of oyster (Crussdstrea grigus). The apparent molecular weight estimated from SDS-PAGE was ca. 28 kDa. The pH optimum of the RNase was 5.0. The RNase released mononucleotides from RNA in the order of 3'-GMP, 3'-AMP, and 3'-UMP. The complete amino acid sequence of RNase Oy was determined, mostly by analyzing the peptides generated by BrCN cleavage or digestion by lysylendopeptidase, staphylococcal V8 protease, and alpha-chymotrypsin. The molecular weight of the protein moiety of RNase Oy deduced from the sequence was 24,359. The sequence of RNase Oy contained two typical histidine residues in segments common to the active site of RNase T2 family enzymes. The locations of six half cystine residues among eight were almost superimposable on those of four known plant RNases of RNase T2 family. The sequence homology between RNase Oy and five fungal and four plant RNases amount, to 43-56 amino acid residues. The amino acid sequence of the N-terminal part of RNase Oy is more similar to those of plant RNases than to those of fungal RNases. This RNase is the first RNase T2 family RNase from mollusc whose primary structure has been elucidated.

Purification and primary structure of a porcine kidney non-secretory ribonuclease

A non-secretory ribonuclease (RNase PK3) was isolated from porcine kidney, and its primary structure was analyzed. RNase PK3 consisted of 126 amino acid residues. The amino acid sequence of RNase PK3 has high sequence homology with non-secretory RNases from human urine and bovine kidney.

Crystal structure of ribonuclease Ms (as a ribonuclease T1 homologue) complexed with a guanylyl-3',5'-cytidine analogue

A ribonuclease T1 homologue, ribonuclease Ms (RNase Ms) from Aspergillus saitoi, has been crystallized as a complex with a substrate analogue GfpC where the 2'-hydroxyl (2'-OH) group of guanosine in guanylyl-3',5'-cytidine (GpC) is replaced by the 2'-fluorine (2'-F) atom to prevent transesterification. The crystal structure of the complex was solved at 1.8-A resolution to a final R-factor of 0.204. The role of His92 (RNase T1 numbering) as the general acid catalyst was confirmed. Of the two alternative candidates for a general base to abstract a proton from the 2'-OH group, His40 and Glu58 were found close to the 2'-F atom, making the decision between the two groups difficult. We then superposed the active site of the RNase Ms/GfpC complex with that of pancreatic ribonuclease S (RNase S) complexed with a substrate analogue UpcA, a phosphonate analogue of uridylyl-3',5'-adenosine (UpA), and found that His12 and His119 of RNase A almost exactly coincided with Glu58 and His92, respectively, of RNase Ms. Similar superposition with a prokaryotic microbial ribonuclease, RNase St [Nakamura, K. T., Iwahashi, K., Yamamoto, Y., Iitaka, Y., Yoshida, N., & Mitsui, Y. (1982) Nature 299, 564-566], also indicated Glu58 as a general base. Thus the present comparative geometrical studies consistently favor, albeit indirectly, the traditional as well as the most recent notion [Steyaert, J., Hallenga, K., Wyns, L., & Stanssens, P. (1990) Biochemistry 29, 9064-9072] that Glu58, rather than His40, must be the general base catalyst in the intact enzymes of the RNase T1 family.

Isolation and characterization of a major allergenic component (gp55) of Aspergillus fumigatus

IgE class antibodies specific for antigens in a water-soluble extract of Aspergillus fumigatus (strain NHL-5759) were analyzed by immunoblotting with sera from patients with allergic bronchopulmonary aspergillosis. All the sera tested were reactive with a major 50 to 60 kd protein in the extract. This allergen, designated gp55, was purified by gel filtration and preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The antigen was found to be present in the water-soluble extract in the form of a complex composed of approximately eight molecules of gp55. The carbohydrate and phosphate content of the purified antigen were 23.1% and 0.46%, respectively. The molar ratio of mannose to galactose residues was 2.76:1, and the protein was glycosylated predominantly with N-linked oligosaccharides. The serologic activity of the gp55 antigen was abolished by treatment with nonspecific protease (Pronase) but not by treatment with sodium metaperiodate or endoglycosidases. Thus the major antigenic site of the glycoprotein is located within its peptide moiety. The antigen itself displayed no chymotryptic or tryptic activity. The amino acid sequence of the 20 N-terminal residues of the antigen (ATPHEPVFFSWDAGAVTSFP) is different from that of any other protein previously reported.

[A case of hereditary motor and sensory neuropathy (HMSN type 2) with bilateral recurrent nerve palsy]

An atypical case of hereditary motor and sensory neuropathy (HMSN) type 2 with cerebellar ataxia, hand tremor and bilateral recurrent nerve palsy was described. The patient was a 57-year-old man who complained of dyspnea, stridor , hoarseness during exercise and snored heavily during sleep since he was 20 years old. These symptoms and signs were slowly progressive. He had difficulty in breathing even at resting state when he was 54 years old and since then, he noticed muscle wasting of his hands and feet. Neurological examinations on admission revealed pes cavus, scoliosis, distal muscular atrophy in his four extremities, especially severe in bilateral lower limbs. Deep tendon reflexes were diffusely depressed. The fiberscopic examination demonstrated the limitation of bilateral vocal cord abduction and his tongue was slightly atrophic. Fine postural tremor was found in bilateral hands. Mild limb and truncal ataxias were also noted. Blood pCO2 level was elevated to 66% although FEV1.0% and vital capacity were within normal limits. Peripheral nerve conduction velocities were almost normal, though distal terminal latencies were slightly prolonged and amplitudes of evoked potentials were markedly decreased. The sural nerve biopsy studies revealed the chronic axonal or neuronal degeneration of both large and small myelinated fibers. From the clinical, electrophysiologic and histopathologic findings, the diagnosis of HMSN type 2 with bilateral recurrent nerve palsy and other atypical neurological findings was made. It is practically important to evaluate the presence or absence of vocal cord paralysis in the patients with HMSN from clinical viewpoints.

Characterization of poly C preferential ribonuclease from chicken liver

Poly C preferential RNase previously reported by Levy and Karpetsky [J. Biol. Chem. 255, 2153-2159 (1980)] and Miura et al. [Chem. Pharm. Bull. 32, 4053-4060 (1984)] was extensively purified from chicken liver to homogeneity as determined by SDS-PAGE (RNase CL2). The poly C preference over poly U was slightly higher than that of bovine pancreatic RNase A. However, the kinetic constants for 8 dinucleoside phosphates, CpY and UpY (Y = one of A, G, U, and C) as substrates showed that RNase CL2 was preferential for cytidylic acid, but less so than RNase A, and the influence of Y base on the rate of hydrolysis of CpY or UpY was less marked than in the case of RNase A. The primary structure of RNase CL2 was determined. The molecular weight calculated from the sequence was 13,420. Comparison of the amino acid sequence of RNase CL2 with those of other vertebrate RNases showed that RNase CL2 is a member of the RNase A family, but is not a non-secretory RNase. It retains 3 disulfide bridges of RNase A, but Cys65-Cys72 of RNase A is missing. As for the active site, the amino acid residues of the P0 and P1 sites of RNase A are completely conserved. Among the B1 site components, Thr45 (RNase A numbering) is conserved, but Phe120 and Ser123 are substituted by Leu and Thr, respectively. Among the B2 site residues, Gln69, Asn71, and Glu111 are substituted by other amino acids.

A novel surface photo-graft polymerization method for fabricated devices

This paper presents a new photo-graft polymerization method that permits surface modification of complex shaped devices. The principle is based on photochemistry of the dithiocarbamate group, as a polymerization initiator-transfer agent-terminator (iniferter), which is capable of photochemical dissociation into a radical pair. The procedure is as follows: first, coating of a photosensitive polymer on a substrate, and subsequent ultraviolet (UV) light irradiation in the presence of a monomer. The photosensitive polymer prepared was a radical copolymer of styrene and vinylbenzyl N,N-diethyldithiocarbamate. Surface graft polymerization of a water soluble monomer (N,N-dimethylacrylamide) on poly(ethylene terephthalate) pre-coated with the photosensitive polymer was achieved. Because the photopolymerization proceeded via a living radical polymerization, the control of molecular weight of the grafted polymer was feasible. This was quantitatively observed by graft polymerization on a quartz crystal microbalance (QCM) that can detect the weight increase with the sensitivity of ng-order. Two-dimensional patterning of cultured cells was demonstrated to show how surface grafted polymerization is limited on UV light irradiation portions with dimensionally micron order precision.

Amino acid sequence of an intracellular, phosphate-starvation-induced ribonuclease from cultured tomato (Lycopersicon esculentum) cells

The primary structure of an intracellular ribonuclease (RNase LX) from cultured tomato (Lycopersicon esculentum) cells has been determined. Previous studies have shown that the protein is located inside the tomato cells but outside the vacuoles and that its synthesis is induced after depleting the cells for phosphate [Löffler, A., Abel, S., Jost, W., Beintema, J. J., Glund, K. (1992) Plant Physiol. 98, 1472-1478]. Sequence analysis was carried out by analysis of peptides isolated after enzymatic and chemical cleavage of the protein. RNase LX consists of 213 amino acids and has a molecular mass of 24300 Da and an isoelectric point of 5.33. The enzyme contains 10 half-cystines and there are no potential N-glycosylation sites detectable in the sequence. RNase LX, as compared to an extracellular tomato RNase (RNase LE), which is also phosphate regulated and the amino acid sequence of which was recently established [Jost, W., Bak, H., Glund, K., Terpstra, P. & Beintema, J. J. (1991) Eur. J. Biochem. 198, 1-6] has 60% of all amino acids identical and in identical positions, revealing a high degree of similarity between both proteins. In contrast to RNase LE, RNase LX has a C-terminal extension of nine amino acids. The C-terminal tetrapeptide HDEF may be a retention signal of the protein in the endoplasmic reticulum.

Maturational changes of urinary growth hormone excretion in the premature infant

High plasma GH concentrations are observed in the newborn infant. To characterize the maturational change of GH secretion in premature infants, we serially measured 24-h urinary GH excretion in 30 premature infants. The gestational age ranged from 25-37 weeks and birth weight from 468-2415 g. Urinary GH excretion at 1 week of age was negatively correlated with gestational age, birth weight, and length of infants with adequate intrauterine growth. In the infants with 27 weeks of mean gestation (range, 25-28 weeks) mean urinary GH excretion was highest (6.1 micrograms/day) at the first week, decreased to 1.2 micrograms/day by the fourth week, and remained between 0.05 and 0.18 micrograms/day thereafter. When compared to the corresponding conceptional age, there was no postnatal difference in the pattern of GH excretion between infants with 27 and 31 (range, 29-32) weeks of mean gestational age. Persistent hyperexcretion of GH was observed in 4 of the 5 infants with intrauterine or postnatal growth retardation. Our results suggest that the postnatal change of 24-h urinary GH excretion is similar to ontogenic changes of plasma GH in fetus, and GH may have some effects on postnatal growth in premature infants.

Purification, some properties, and primary structure of base non-specific ribonucleases from Physarum polycephalum

Two ribonucleases (RNase Phya and RNase Phyb) were purified to homogeneity on SDS-PAGE from the culture filtrate of the fungus Physarum polycephalum. The apparent molecular weights of RNases Phya and Phyb were about 20,000. The pH optima of these two RNases were around 4.5-4.75. The RNases released mononucleotides from RNA in the order of 3'-GMP, 3'-AMP, and 3'-pyrimidine nucleotides. RNase Phya and RNase Phyb have the N-terminal amino acid sequences STSFD--- and KSTSF--, respectively. This finding and the similar amino acid compositions of both RNases indicated that they might share the same protein moiety except for the N-terminus Lys. The complete primary structure of RNase Phyb was determined, mostly by analysis of the peptides generated by trypsin, V8 protease, and lysylendopeptidase digestions. The molecular weight of the protein moiety was 19,704. The locations of four half cystine residues were almost superimposable on those in five known fungal RNase T2 family RNases, but two others were not. The sequence homology between RNase Phyb and five known fungal RNases amounted to 53-59 residues, which are concentrated around the three histidine residues, supposed to form the active site in enzymes of the RNase T2 family. However, the amino acid sequence of RNase Phyb more closely resembles those of plant RNases such as RNases from Nicotiana alata [McClure, B.A. et al. (1989) Nature 342, 955-957], tomato [RNase Le, Yost et al. (1991) Eur. J. Biochem. 198, 1-6], and Momoridica charantia [RNase MC1, Ide et al. (1991) FEBS Lett. 284, 161-164].

Rapid degradation of cucumber cotyledon lipoxygenase

The lipoxygenase activity from cucumber cotyledons grown with their embryonic axis was separated into two fractions having M(r)s of 90,000 and 96,000, respectively, by hydrophobic chromatography. However, from de-embryonated cucumber cotyledons, only one form of lipoxygenase having a M(r) of 90,000 was purified. The three lipoxygenases could not be distinguished from each other either immunologically or by their enzymatic properties. Furthermore, peptide maps of the 90,000 and 96,000-lipoxygenases were identical. In a crude homogenate of cucumber cotyledons, the 96,000-lipoxygenase was rapidly degraded to the 90,000-form. Thus, it was inferred that the 90,000-lipoxygenase was probably the 96,000-form which had lost a peptide fragment of 6,000. It is suggested that there is a specific proteolytic activity for the degradation of 96,000-lipoxygenase. Estimation of changes in the proteolytic activity during seedling growth suggests that the activity at least partly contributes to the rapid in vivo degradation of cucumber cotyledon lipoxygenase.

Induction of metallothionein in a human astrocytoma cell line by interleukin-1 and heavy metals

The effects of cytokines and heavy metals on the expression and localization of metallothioneins (MTs) within U373MG astrocytoma cells were analyzed by using indirect immunofluorescence using a monoclonal anti-MT antibody (MT45). IL-1, CdCl2 (50 microM) or ZnCl2 (500 microM) remarkably augmented intracellular MT levels, whereas IL-6 or 10 microM of ZnCl2 showed no inducing activity. From 24 to 48 h after the addition of CdCl2 or IL-1, immunoreactive MTs were found in the cytoplasm and the nucleus. After 72 h, immunoreactive MTs accumulated in a granular form near the cell surfaces in the presence of CdCl2 (50 microM) or IL-1 plus ZnCl2 (10 microM). However, this accumulation was not observed when only IL-1 was added. Thus, Zn2+ facilitated the appearance of the granular form of immunoreactive MTs at a concentration where they do not induce MTs by themselves.

Role of Asp51 and Glu105 in the enzymatic activity of a ribonuclease from Rhizopus niveus

The active site of a base non-specific RNase from Rhizopus niveus (RNase Rh), consists of three histidine residues and one carboxyl group [Ohgi, K. et al. (1992) J. Biochem. 111, 132-138]. In order to identify this acidic amino acid residue, we chose Asp51 and Glu105 as candidates based on a comparison of the primary structures of four fungal RNases and self-incompatibility factors of Nicotiana alata which belong to the RNase T2 family. We substituted these amino acid residues with other amino acids by site-directed mutagenesis, and determined the enzymatic properties of the mutated enzymes. The enzymatic activities of E105Q, E105D, and E105A mutant enzymes were decreased markedly, but those of D51N, D51E, and D51A were decreased only slightly when RNA was used as a substrate. Therefore we concluded that Glu105 is related to the catalytic function. Kinetic constants for the enzymatic activity of E105Q and E105D toward ApU suggest that the proper size and negative charge of side chain groups are important for the catalysis of RNase Rh. However, the enzymatic activity of D51N toward ApU, but not toward UpU, decreased markedly. Therefore, we suggest that Asp51 is one of the amino acid residues forming the base recognition site. The substitution of Asp51 by Asn causes the enzyme to be more guanine nucleotide-preferential.

The detection of a mutation of CD18 gene in bovine leukocyte adhesion deficiency (BLAD)

Two calves (5 and 9 months old) affected with pneumonia and gingivitis were also diagnosed as having bovine leukocyte adhesion deficiency (BLAD). The gene of leukocyte adhesion molecule CD18 in these BLAD calves and their dams (carrier) were examined by means of polymerase chain reaction (PCR) and digestion of restriction endonuclease. The splicing in mRNA coded CD18 reported in human LAD was not recognized in BLAD on the basis of the results of PCR amplification. The region including the portion of point mutation, which corresponded to the region reported in the human patient, was amplified by PCR, and the PCR product was then digested with Taql. An obvious difference was recognized in the pattern of digestion among healthy calves, BLAD calves and their dams. In BLAD, therefore, the point mutation reported in human patients was strongly suggested. Moreover it may be a method able to be used in detecting the carrier.

Crystal and molecular structure of RNase Rh, a new class of microbial ribonuclease from Rhizopus niveus

The crystal structure of RNase Rh, a new class of microbial ribonuclease from Rhizopus niveus, has been determined at 2.5 A resolution by the multiple isomorphous replacement method. The crystal structure was refined by simulated annealing with molecular dynamics. The current crystallographic R-factor is 0.200 in the 10-2.5 A resolution range. The molecular structure which is completely different from the known structures of RNase A and RNase T1 consists of six alpha-helices and seven beta-strands, belonging to the alpha+beta type structure. Two histidine and one glutamic acid residues which were predicted as the most probably functional residues by chemical modification studies are found to be clustered. The steric nature of the active site taken together with the relevant site-directed mutagenesis experiments (Irie et al.) indicates that: (i) the two histidine residues are the general acid and base; and (ii) an aspartic acid residue plays a role of recognizing adenine moiety of the substrate.

Alopecia universalis treated with oral cyclosporine A and prednisolone: immunologic studies

Alopecia universalis is a refractory condition. Although the cause of this disease is unknown, immunologic abnormalities have recently been suspected. Thus, we treated six cases of refractory alopecia universalis with immunotherapy. Oral administration of cyclosporine A (2.5 mg/kg) and prednisolone (5 mg/day) resulted in marked symptomatic improvement. Cyclosporine A did not produce any side effects because the administered dosage was relatively low. At present, more than 6 months after the cessation of treatment, recurrence of alopecia has not been seen. Oral administration of low-dose cyclosporine A and prednisolone is considered to be an effective treatment for this disease. Immunologic examination of peripheral blood demonstrated improvement of immunologic function. In particular, CD8-positive T cells, NK cells, and C3, which had been reduced, were increased. A reduction in active CD4 cells, eosinophils, and circulating immune complexes was observed. Histology with fluorescent antibodies showed T-cell infiltration around the hair matrixes. This phenomenon was no longer observed after treatment. These improvements in immunologic function were seen in parallel with the resolution of the clinical symptoms, indicating that immunologic abnormalities are related to this disease.

Effect of wavelength on spatial measurements of light scattering for the measurement of pork quality

White light from a xenon arc was focused onto the upper surface of 25-mm-thick transverse sections of pork longissimus muscle. A servo motor moved an optical fiber across the lower surface of the muscle to collect transmitted light, which then was passed through a grating monochromator and onto a photomultiplier for spatial measurements of scattering (SMS) and transmittance spectra. The SMS were calculated as the slope of the logarithm of transmittance relative to path length through the sample (which was calculated trigonometrically). Pale, soft, exudative (PSE) pork was measured with an index that included a subjective evaluation of meat color and objective measurements of reflectance, drip loss, and centrifugation fluid loss. The strongest correlation of SMS with PSE was at 610 nm (r = .86, P less than .005) and the strongest correlation of transmittance with PSE was at 650 nm (r = -.95, P less than .005). This supports the use of a red laser at 633 nm for the detection of PSE pork.

Evidence that three histidine residues of a base non-specific and adenylic acid preferential ribonuclease from Rhizopus niveus are involved in the catalytic function

In order to study the structure-function relationship of an RNase T2 family enzyme, RNase Rh, from Rhizopus niveus, we investigated the roles of three histidine residues by means of site-specific mutagenesis. One of the three histidine residues of RNase RNAP Rh produced in Saccharomyces cerevisiae by recombinant DNA technology was substituted to a phenylalanine or alanine residue. A Phe or Ala mutant enzyme at His46 or His109 showed less than 0.03%, but a mutant enzyme at His104 showed 0.54% of the enzymatic activity of the wild-type enzyme with RNA as a substrate. Similar results were obtained, when ApU was used as a substrate. The binding constant of a Phe mutant enzyme at His46 or His109 towards 2'-AMP decreased twofold, but that at His104 decreased more markedly. Therefore, we assumed that these three histidine residues are components of the active site of RNase Rh, that His104 contributes to some extent to the binding and less to the catalysis, and that the other two histidine residues and one carboxyl group not yet identified are probably involved in the catalysis. We assigned the C-2 proton resonances of His46, His104, and His109 by comparison of the 1H-NMR spectra of the three mutant enzymes containing Phe in place of His with that of the native enzyme, and also determined the individual pKa values for His46 and His104 to be 6.70 and 5.94. His109 was not titrated in a regular way, but the apparent pKa value was estimated to be around 6.3. The fact that addition of 2'-AMP caused a greater effect on the chemical shift of His104 in the 1NMR spectra as compared with those of the other histidine residues, may support the idea described above on the role of His104.

Identification of metallothionein in cultured cells by immunoblotting and immunofluorescence using a new monoclonal antibody

A hybridoma clone (MT45-5-3) producing an IgG-class monoclonal antibody specific for metallothioneins (MTs) was established. The monoclonal antibody (MT45) cross-reacted with mouse, rat and rabbit Cd(2+)-induced MTs 1 and 2 and Zn(2+)-induced MT 2 as assessed by enzyme-linked immunosorbent assay. When the antibody was used to detect the MTs transferred to nylon membranes after SDS-polyacrylamide gel electrophoresis, the antibody reacted with cultured human cell MTs as well as rat, mouse and rabbit MTs 1 and 2 even after carboxymethylation. The antibody could be used for the indirect immunofluorescence test for Cd(2+)-induced MTs in cultured human and mouse cells.

[Graduated psychosomatic treatment and quality of life in asthmatics]

We investigated the quality of life (QOL) in 72 patients with bronchial asthma who are under our gradational psychosomatic treatment (GPT) by means of an 11-item questionnaire. The results were summarized as follows: 1) Ninety-two percent of the subjects showed a good understanding of mind-body relations and modified their stressful adaptive patterns. 2) Asthmatic symptoms improved in 86 percent of the subjects. Other symptoms also improved in 72 percent of the subjects. 3) In 81 percent of the subjects, their daily life improved. Furthermore 96 percent of the subjects obtained some advantages through GPT. 4) There were various improvements in psychological states, personal relations and life style in most of the subjects. 5) The attitudes of their families toward the patients improved in 46 percent of the subjects, however 71 percent of the families developed a better understanding of the cause of asthma from the psychosomatic point of view. 6) Most of the subjects with moderate or severe symptoms were considered to have reduced the grade of severity of their symptoms from the doctor's standpoint.

Amino acids and peptides. XXXIII. Synthesis of N-terminal epitope peptides of mammalian metallothioneins (MTs)

In order to determine the fine structure of the mammalian metallothionein (MT) epitope to a monoclonal anti-rat Zn-MT-II antibody (MT 189-14-7), N-terminal peptides of various lengths of mammalian metallothioneins (MTs) were synthesized by a conventional solution method using the newly developed beta-2-adamantylaspartate, and their immunological properties were examined. It was found that the N-terminal acetyl group was indispensable for the reaction with the monoclonal antibody and the N-terminally acetylated pentapeptide, Ac-Met-Asp-Pro-Asn-Cys-OH, was the smallest peptide which exhibited a significant reactivity with the antibody.

[Long-term treatment of acromegaly and gigantism with octreotide (SMS 201-995)]

Twenty-one patients with active acromegaly and two patients with pituitary gigantism were treated with the long-acting somatostatin analogue octreotide (100-600 micrograms/day, sc, two or three times daily or 300-1500 micrograms daily by intermittent sc infusion) for 9-63 months. There was rapid clinical improvement. The fasting plasma GH levels were significantly suppressed (less than 50% of the values before treatment) in 17 patients and were normalized (less than 5 ng/ml) in 6 patients (27.3%). Plasma IGF-I levels were lowered by 50% and were normalized in 7 out of 18 cases. The effect of octreotide on pituitary tumor size was evaluated in 13 patients. In 4 cases, the shrinkage of the pituitary tumor was detected by computed tomographic scans and/or magnetic resonance imaging studies. The drug was generally well tolerated. However, there were probably newly formed gallstones in two patients during the therapy. Our study suggests that octreotide is an effective and relatively safe new approach for treating active acromegaly and gigantism.

Fat characteristics of pigs fed fish oil containing eicosapentaenoic and docosahexaenoic acids

Sixteen pigs averaging 81.4 kg were assigned to a control diet and three test diets containing 2, 4, or 6% fish oil. Subcutaneous fat samples from the loin were obtained by biopsy at weekly intervals and analyzed for fatty acid composition. The pigs were maintained on the diets (ad libitum access to feed) for 4 wk before slaughter at an average weight of 107.8 kg. Outer and inner layers of backfat, perirenal fat, and intermuscular fat were obtained from the carcass and analyzed for physicochemical characteristics. In the biopsy samples, the contents of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in fat from pigs fed fish oil began to increase during the 1st wk. Rates of increase were greater during the first 2 wk than during the last 2 wk. In the carcass samples, the increase in EPA and DHA in all fat tissues analyzed became greater as the supplemental levels of fish oil were increased in the diet, whereas oleic and linoleic acids tended to be decreased by increases in EPA and DHA. Color of fat was not significantly different among the control and fish oil groups. With the increase in fish oil in the diet, the hardness of fat measured with a texturometer was decreased. The refractive index and the iodine number were increased. As for differences among anatomical locations, it was noted that EPA and DHA contents of perirenal fat were higher than those of backfat and intermuscular fat. These results indicate that porcine adipose tissues rich in EPA and DHA can be produced by feeding fish oil.

Histochemical and fine structural study of bone of ipriflavone-treated rats

Bone labeling, histochemical, and fine structural studies were performed in order to clarify the effects of ipriflavone (IP) on rat bone tissue in vivo and in vitro. Labeling experiments showed a slight increase in bone formation during 3 days' administration. It was also noted that many osteoclasts detached from the bone surface at 1, 2, and 6 hours after administration in vivo. In addition, irregular localization of tartrate-resistant acid phosphatase (TRACPase) activity was observed in osteoclasts. Fine structurally, IP-treated osteoclasts exhibited irregularity in their ruffled borders, as reported in calcitonin administration, and many enlarged rough endoplasmic reticuli and vacuoles were observed. However, osteoclasts at 12 hours after administration, as well as the control, indicated recovery features from the effect of IP. Osteoblast proliferation and differentiation led to increasing alkaline phosphatase activity (ALPase) with time as well as the development of rough endoplasmic reticuli and Golgi apparatus with well-developed fine structure. These findings imply active synthesis of bone matrix. In our in vitro experiment, osteoclasts and osteoblasts displayed histochemical and fine structural characteristics similar to those observed in our in vivo experiment. Moreover, fewer TRACP-positive mononuclear cells were observed after 24-hour culture with IP than with the control. These results suggest that IP inhibits directly and/or indirectly differentiation and activity of osteoclasts and also promotes differentiation of osteoblast-lineage cells and their bone-forming activity.

Blocking type immunoglobulins in patients with nongoitrous primary hypothyroidism in area of iodine deficiency

We have evaluated the role of circulating serum immunoglobulins (IgG) which inhibit the growth of thyroid in the etiology of thyroid atrophy in endemic cretinism. Twenty nongoitrous cretins (13 women and 7 men, age range: 9-33) were classified on the basis of clinical criteria for cretinism in China. They were born and living in an iodine deficient area, Xinjiang, northwest China. Antimicrosomal antibody titers were negative in all serum. Nine patients (seven women and two men; age range: 11-23) were biologically primary hypothyroid. Seven subjects were of a myxedematous form and two subjects were of a mixed form. We have studied thyroid-growth inhibiting immunoglobulin (TGII) activity that was measured as an inhibitory effect of 4 mg/ml IgG on TSH-induced [3H]-thymidine incorporation into the DNA of a rat thyroid follicular cell line, FRTL5 cells. Six (five women and one man) out of the nine patients with primary hypothyroidism (66.7 percent) had TGII. We also measured other growth-blocking IgG that inhibited [3H]-thymidine incorporation into DNA stimulated by insulin-like growth factor-I (IGF-I), a growth factor working through a cAMP-independent pathway. Five (three women and two men) out of nine patients (55.6 percent) with nongoitrous primary hypothyroidism had IGF-I-blocking IgG. These results indicate that TGII plays an important role in atrophy of the thyroid in spite of increased serum TSH concentrations, and IgG which inhibits thyroid growth stimulated by IGF-I also might play a role in thyroid atrophy in some endemic cretins.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term follow-up investigation of the effects of the biopsychosocial approach (BPSA) to bronchial asthma

The recent rapid increase in the number of allergic patients is becoming a social problem. Studies of the causes of this phenomenon involve various fields, with much attention focused on finding new antigens in food, air, articles encountered in daily living, etc. Recent studies of psychoneuroimmunology (PNI) also suggest a strong influence of emotions on allergic reactions. The number of allergic patients is increasing in all civilized countries without exception, and the stress prevalent in modern civilized society is related to this increase. Modern allergology does not yet have sufficient countermeasures for such stress states. We applied a biopsychosocial approach (BPSA) to treatment programs for allergic disease, incorporating treatment of physical and psychosocial problems en bloc. We studied the long-term effects of BPSA therapy on 82 patients who were treated for more than 3 months in the hospital and were examined 2 to 3 years after discharge. Results showed that more than 80% of patients maintained improvement and 45% of those with intractable asthma were able to withdraw from steroid hormones. BPSA achieved better results than those with standard medication administered only to the body. Improvements after treatment included physical changes, normalization of MV (microvibration) type, decreased levels of plasma histamine, and normal circadian rhythms of lymphocyte subsets. These changes reflect part of the physical mechanisms by which BPSA improves asthma symptoms. From a psychological view point, the patients' feelings, personal relations, behavior, etc. were changed after BPSA, allowing a new life style and improved QOL. It is important for asthma patients to maintain good overall condition over long periods. After BPSA, 80% of our patients were able to do so. It is difficult for the therapist to approach asthma from different aspects at once, including biological, psychological, and social, so we developed a five-stage program of BPSA therapy and found that this obtained favorable results.

Isolation, characterization, and primary structure of a base non-specific and adenylic acid preferential ribonuclease with higher specific activity from Trichoderma viride

In order to elucidate the structure-function relationship of RNases belonging to the RNase T2 family (base non-specific and adenylic acid-preferential RNase), an RNase of this family was purified from Trichoderma viride (RNase Trv) to give three closely adjacent bands with RNase activity on slab-gel electrophoresis in a yield of 20%. The three RNases gave single band with the same mobility on slab-gel electrophoresis after endoglycosidase F digestion. The enzymatic properties including base specificity of RNase Trv were very similar to those of typical T2-family RNases such as RNase T2 from Aspergillus oryzae and RNase M from A. saitoi. The specific activity of RNase Trv towards yeast RNA was about 13-fold higher than that of RNase M. The complete primary structure of RNase Trv was determined by analyses of the peptides generated by digestion of reduced and carboxymethylated RNase Trv with Staphylococcus aureus V8 protease, lysylendopeptidase and alpha-chymotrypsin. The molecular weight of the protein moiety deduced from the sequence was 25,883. The locations of 10 half-cystine residues were almost superimposable upon those of other RNases of this family. The homologies between RNase Trv and RNase T2, RNase M, and RNase Rh (Rhizopus niveus) were 124, 132, and 92 residues, respectively. The sequences around three histidine residues, His52, His109, and His114, were highly conserved in these 4 RNases.

[Psychosomatic study of inhalation therapy in patients with bronchial asthma. II. Relationship between subjective self assessment of dyspnea and peak expiratory flow rates]

The degree of dyspnea when using metered-dose inhalers (MDIs), and the relationship between subjective self assessments and objective peak expiratory flow rates were examined by means of visual analogue scales and mini wright peak flow meters in 16 subjects with asthma. Three subjects who were neurotic in character were found to have a poor perception of the degree of airway obstruction after inhalation compared with objective changes in their condition. Two subjects, one neurotic and one alexithymic, assessed the degree of dyspnea to be worse after inhalation, when objectively there were few changes. However, one neurotic subject perceived an improvement in his condition when, in fact, there was little change. Furthermore, some severe cases used MDIs in the rogressive state of airway obstruction. In conclusion, we must pay attention to patients' characters when determining treatment in order to prevent overuse of MDIs or delays in treatments including the use of MDIs.

[Psychosomatic study of inhalation therapy in patients with bronchial asthma. I. Evaluation by questionnaire]

We investigated the use of metered-dose beta agonist inhalers (MDIs) by means of 17-item questionnaires from the standpoint of psychosomatic medicine in 56 subjects with bronchial asthma. The results can be summarized as follows: 1) Many asthmatics with neurotic characters used MDIs frequently; Thirteen percent of them suffered adverse effects. The number of times the inhalers were used increased in proportion to the severity and the duration of illness. Fifteen percent of the subjects used MDIs frequently because of anxiety. 2) Fifty percent of the subjects, most of them had neurotic or alexithymic characters, used MDIs without suffering from dyspnea or wheezes; the subjects who used MDIs because of anxiety increased in proportion to the duration of illness. 3) Seventy eight percent of the subjects were anxious about asthmatic attack when they did not carry any MDI; sixty two percent of the subjects, most of them had neurotic or alexithymic characters, actually experienced asthmatic attack. 4) Seventy three percent of the subjects used MDIs secretly; sixty percent of the subjects did not like to inhale in the presence of others. 5) There were some subjects who acted incorrectly on or after asthmatic attack when MDIs were not effective.

Purification and characterization of a nuclease from Lentinus edodes

An endonuclease with 3'-nucleotidase activity (nuclease Le1) was purified from fruit bodies of Lentinus edodes in a single band on sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The apparent molecular weight of nuclease Le1 was about 27000. The nuclease was inactivated in the presence of ethylenediaminetetraacetic acid (EDTA) and reactivated by the addition of Zn2+. Hydrolysis of poly U by the nuclease showed many intermediate size oligomers prior to the formation of 5'-uridine monophosphate (UMP). Therefore, it was concluded that nuclease Le1 was a Zn(2+)-endonuclease similar to P1-nuclease from Penicillium citrinum. The nuclease was very sensitive to ionic strength, but pH-profiles of the hydrolysis of four 3'-nucleotides were very similar to those of P1 nuclease from P. citrinum.

Purification and properties of a novel surface-active agent- and alkaline-resistant protease from Bacillus sp. Y

In the course of a search for an alkaline stable protease for industrial use, an alkaline protease (protease BYA) was isolated from an alkalophilic Bacillus sp. Y, and its properties were characterized. Its optimum pH was pH 10.0-12.5, when casein was used as a substrate. In addition to the stability of protease BYA at pH 6.5-13.0, it was also very stable towards various surface-active agents, such as sodium dodecyl sulfate and sodium linear alkylbenzene sulfonate. Protease BYA was most active at 70 degrees C. The isoelectric point (pI) of protease BYA was about 10.1. Protease BYA was characterized as a serine protease because of its sensitivity to phenylmethanesulfonyl fluoride and diisopropyl fluorophosphate. The protease seems to be related to proteases of the subtilisin family, such as subtilisin BPN', subtilisin Carlsberg, and No. 221 protease.

Serum profiles of steroid hormones in patients with Cushing's syndrome determined by a new HPLC/RIA method

We developed a method for simultaneously measuring steroid hormones in very small volumes of serum, using a combination of high-performance liquid chromatography (HPLC) and radioimmunoassay (RIA). By this method, aldosterone, cortisol, 11-deoxycortisol, estrone, estradiol, androstenedione, dehydroepiandrosterone, deoxycorticosterone, 17-hydroxyprogesterone, testosterone, pregnenolone, and progesterone could be determined in a single 100-microL aliquot of serum from normal adults and patients with Cushing's syndrome. The steroid profile associated with Cushing's syndrome caused by adrenal adenoma was quite distinct from that associated with the syndrome caused by adrenal hyperplasia. Serum concentrations of androstenedione, dehydroepiandrosterone, estrone, estradiol, 17-hydroxyprogesterone, pregnenolone, and testosterone were significantly higher in patients with adrenal hyperplasia than in those with an adenoma. We compared the results of this HPLC/RIA method with those of 125I RIAs. The use of a HPLC/RIA system to obtain an accurate and sensitive profile of a range of serum steroids, as described here, obviates the need for large volumes of blood.

Serum profiles of steroid hormones in patients with Cushing's syndrome determined by a new HPLC/RIA method

We developed a method for simultaneously measuring steroid hormones in very small volumes of serum, using a combination of high-performance liquid chromatography (HPLC) and radioimmunoassay (RIA). By this method, aldosterone, cortisol, 11-deoxycortisol, estrone, estradiol, androstenedione, dehydroepiandrosterone, deoxycorticosterone, 17-hydroxyprogesterone, testosterone, pregnenolone, and progesterone could be determined in a single 100-microL aliquot of serum from normal adults and patients with Cushing's syndrome. The steroid profile associated with Cushing's syndrome caused by adrenal adenoma was quite distinct from that associated with the syndrome caused by adrenal hyperplasia. Serum concentrations of androstenedione, dehydroepiandrosterone, estrone, estradiol, 17-hydroxyprogesterone, pregnenolone, and testosterone were significantly higher in patients with adrenal hyperplasia than in those with an adenoma. We compared the results of this HPLC/RIA method with those of 125I RIAs. The use of a HPLC/RIA system to obtain an accurate and sensitive profile of a range of serum steroids, as described here, obviates the need for large volumes of blood.

Three-dimensional structure of ribonuclease Ms*3'-guanylic acid complex at 2.5 A resolution

The crystal structure of ribonuclease Ms*3'-guanylic acid complex has been determined by molecular replacement methods based on the known structure of ribonuclease T1. The pattern of hydrogen-bonds between the enzyme and the guanine base is similar to that discovered by Arni et al. [( 1988) J. Biol. Chem. 263, 15358-15368] in the crystal structure of ribonuclease T1*2'-guanylic acid complex. As for the possible general base in the trans-phosphorylation step of the catalysis, 0 epsilon 1 of Glu57 is within the hydrogen-bond distance (2.7 A) of the 2'-0 of the nucleotide while N epsilon 2 of His39 is significantly more distant (3.4 A) from the 2'-0.

Influence of perinatal factors and sampling methods on TSH and thyroid hormone levels in cord blood

To evaluate the effect of perinatal factors and sampling methods on thyroid stimulating hormone (TSH) and thyroid hormone levels in cord blood, serum TSH, free thyroxine (FT4) and free triiodothyronine (FT3) concentrations were measured in 124 healthy term neonates. Eighty-eight infants were born in normal vaginal deliveries, 25 were delivered by vacuum extractor and 11 by Cesarean section. There was no significant difference among the three infant groups in the mean TSH levels. Birth weight, the infant's sex, duration of labor and uterotonic agents had no effect on cord serum TSH and free thyroid hormone levels in the neonates born by normal vaginal delivery. To assess the adequacy of specimen collection, mixed cord blood samples, obtained by a direct application of cord on a filter paper, and venous blood withdrawn with a plastic syringe were collected in another 200 infants. There was a significant linear correlation in the TSH concentration in mixed cord blood and cord venous serum from the same individuals, while a poor correlation was found in T4 values from two specimens. Our results suggest that the TSH value in cord blood is less influenced by perinatal factors, including the sampling method, and the mixed cord blood collected by this technique might be a feasible alternative specimen for a TSH screening program with cord blood which is useful in countries where neonatal blood is not available.

Comparative base specificity, stability, and lectin activity of two lectins from eggs of Rana catesbeiana and R. japonica and liver ribonuclease from R. catesbeiana

Two lectins with RNase activity obtained from eggs of Rana catesbeiana and R. japonica and RNase obtained from R. catesbeiana liver show 65-83% protein homology. The base specificity of these frog proteins was studied with 8 dinucleoside phosphates as substrates and 8 nucleotides as inhibitors. The base specificities of the B1 and B2 sites of these proteins are U greater than C and G greater than U greater than A, C, respectively. The three frog proteins are more resistant than RNase A to heat treatment, guanidine-HCl and pH-induced denaturation; i.e., they retain their native conformation up to at least 70 degrees C at pH 7.5. Differences in stability and base specificity among RNase A and the three frog proteins are discussed in relation to the primary structures. Although the two lectins agglutinate tumor cells (e.g., Ehrlich, S-180 and AH109A ascites carcinoma cells), the liver RNase has no such activity. Agglutination of AH109A cells by the two lectins is inhibited by nucleotides. Our results indicate that the agglutination sites are not identical with, but are related to, the active sites of the three frog proteins.

Expression of RNase Rh from Rhizopus niveus in yeast and characterization of the secreted proteins

The full-length cDNA encoding RNase Rh, which is secreted extracellularly by Rhizopus niveus, was isolated and its nucleotide sequence was determined. It was placed under control of the promoter of the glyceraldehyde 3-phosphate dehydrogenase gene of Saccharomyces cerevisiae in a high expression vector in yeast. Since yeast cells transformed by this plasmid poorly secreted RNase into the medium, the plasmid pYE RNAP-Rh was constructed, in which the signal sequence of RNase Rh was replaced by the prepro-sequence of aspartic proteinase-I, one of the extracellular enzymes secreted by R. niveus. Yeast cells harboring pYE RNAP-Rh produced RNase efficiently (ca. 40 micrograms/ml) into the medium. The product was a mixture of six enzymes (RNase RNAP-Rhs) having 3, 5, 9, 13, 14, and 16 additional amino acid residues attached to the amino terminus of the mature RNase Rh. The major product was the RNase with three additional amino acids at the amino terminus. Limited digestion of RNase RNAP-Rhs with staphylococcal V8 protease succeeded in shortening the various lengths of extra amino acid residues attached to the amino terminus of RNase Rh, yielding an RNase that has 3 additional amino acids at the amino terminus. It has been named RNase RNAP-Rh. The RNase RNAP-Rh showed the same specific activity and CD spectra as those of RNase Rh, suggesting that the two have similar conformations to each other around aromatic amino acid residues and the peptide backbone.

Formation of pyrazine derivatives from D-glucosamine and their deoxyribonucleic acid (DNA) strand breakage activity

Two pyrazine derivatives [fructosazine (3) and deoxyfructosazine (6)] were simultaneously formed in a solution of D-glucosamine hydrochloride under various conditions. They showed deoxyribonucleic acid (DNA) strand breakage activity in plasmid pBR322 comparable to that of D-glucosamine. The DNA strand breakage by fructosazine (3) was stimulated by Cu2+.

Primary structure of a nuclease (nuclease PA3) from a Penicillium sp

The complete primary structure of a nuclease from a Penicillium sp. [nuclease PA3 (Kazama et al., Chem. Pharm. Bull., 38, 3081 (1990)] was determined. The sequencing was done by analysis of the peptides generated by digestion of reduced and carboxymethylated nuclease PA3 (RCM nuclease PA3) with lysylendopeptidase, and by digestion with staphylococcal V8 protease or chemical cleavage with BrCN. It consisted of 270 amino acid residues and carbohydrate moieties attached to the 92nd, 138th, 184th, and 197th asparagine residues. The molecular weight of the protein moiety deduced from the sequence was 29,211. It contains four half cystine residues. The amino acid sequence was identical with that of P1 nuclease from Penicillium citrinum [K. Maekawa, S. Tsunasawa, G. Dibo, and F. Sakiyama, Abstracts of Papers, the 62nd Meeting of the Biochemical Society of Japan, Seikagaku, 61, 1013 (1989)] except that the 190th Thr residue was Ile in P1 nuclease.