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H Yasueda

Publications and source records attributed to H Yasueda.

At least 37 records · Page 2Linked to original sources
PubMed1999

Bacillus subtilis yckG and yckF encode two key enzymes of the ribulose monophosphate pathway used by methylotrophs, and yckH is required for their expression.

The ribulose monophosphate (RuMP) pathway is one of the metabolic pathways for the synthesis of compounds containing carbon-carbon bonds from one-carbon units and is found in many methane- and methanol-utilizing bacteria, which are known as methylotrophs. The characteristic enzymes of this pathway are 3-hexulose-6-phosphate synthase (HPS) and 6-phospho-3-hexuloisomerase (PHI), neither of which was thought to exist outside methylotrophs. However, the presumed yckG gene product (YckG) of Bacillus subtilis shows a primary structure similar to that of methylotroph HPS (F. Kunst et al., Nature 390:249-256, 1997). We have also investigated the sequence similarity between the yckF gene product (YckF) and methylotroph PHI (Y. Sakai, R. Mitsui, Y. Katayama, H. Yanase, and N. Kato, FEMS Microbiol. Lett. 176:125-130, 1999) and found that the yckG and yckF genes of B. subtilis express enzymatic activities of HPS and PHI, respectively. Both of these activities were concomitantly induced in B. subtilis by formaldehyde, with induction showing dependence on the yckH gene, but were not induced by methanol, formate, or methylamine. Disruption of either gene caused moderate sensitivity to formaldehyde, suggesting that these enzymes may act as a detoxification system for formaldehyde in B. subtilis. In conclusion, we found an active yckG (for HPS)-yckF (for PHI) gene structure (now named hxlA-hxlB) in a nonmethylotroph, B. subtilis, which inherently preserves the RuMP pathway.

Aldehyde-Lyases↗
PubMed1999

[A study of aggravation of atopic dermatitis during Japanese cedar pollen season--correlation with grades of dermatitis on face and Cry j 1 specific IgE].

We studied influence of Japanese cedar pollen (Jcp) on aggravation of atopic dermatitis (AD) during the pollination season. 48.5% of 97 patients with atopic dermatitis showed aggravation of dermatitis during the pollination season and 85% of them had Japanese cedar pollinosis, whereas only 44% of AD patients without the aggravation had the pollinosis. There was no difference of grades of dermatitis on face between the groups with or without the aggravation. Furthermore, we measured specific IgE to Jcp and Cry j 1, a major allergen of Jcp, by ELISA in the sera from the 54 patients with AD. The levels of specific IgE antibodies to both allergens in the group with the pollinosis were significantly higher than in the group without the pollinosis. However, significant difference of those was not recognized between the groups with or without the aggravation of AD. Therefore, our study has suggested that Japanese cedar pollen is likely to be one of causes of seasonal aggravation of AD in individuals sensitized to the pollen, and some other factors, e.g. Jcp-specific T cells, might play an important roll in addition to the Jcp-specific IgE.

Adolescent↗
PubMed1998

Identification and cloning of two novel allergens from the lipophilic yeast, Malassezia furfur.

Two novel allergens, designated Mal f 2 and Mal f 3 according to the WHO/IUIS Allergen Nomenclature Subcommittee recommendation, were isolated from the lipophilic yeast Malassezia furfur cell extracts and the genes coding for those were cloned. Mal f 2 and Mal f 3 had apparent molecular weights of 21 kDa and 20 kDa, respectively, on SDS-PAGE under reducing conditions. The identified cDNA clone of Mal f 2 encoded an open reading frame of 177 amino acid residues. Fifty-one percent identity was found between the Mal f 2 and Mal f 3 sequences. Comparison of the Mal f 2 and Mal f 3 sequences with known protein sequences revealed that they had sequence homology with two peroxisomal membrane proteins of Candida boidinii and an Aspergillus fumigatus allergen, Asp f 3. In RAST, both Mal f 2- and Mal f 3-specific IgE antibodies could be detected in approximately 70 % of sera from M. furfur sensitized patients with atopic dermatitis.

Allergens↗
PubMed1998

Preventive effect of bedding encasement with microfine fibers on mite sensitization.

BACKGROUND: The indoor levels of mite allergens are known to determine the thresholds of sensitization and asthma exacerbation. However, the method for preventing mite sensitization by reducing the levels of house dust mites (HDMs) is not well established. OBJECTIVE: We investigated whether mite-blocking bedding encasing made from microfine fibers can prevent infants from being sensitized to HDMs. METHODS: Fifty-seven Japanese infants with atopic dermatitis who had high levels of IgE antibodies against either egg white, cow's milk, or soybean (but not against HDMs) were randomly chosen and divided into two groups. Thirty families of atopic infants (group A) were instructed to decrease HDMs by controlling the indoor environment, including bedding cleaning, whereas 27 families receiving the same instructions (group B) were further guided to use the Allerguard encasing for quilts and mattresses of all family members. We repeatedly examined Der p 1 + Der f 1 in the infants' mattresses and anti-Dermatophagoides farinae (Df) IgE in the infants' sera, and we performed skin prick tests with Df extract for 1 year. RESULTS: The mite-blocking encasing markedly reduced the levels of Der p 1 + Der f 1 (3.0 microg/g dust for group A vs 0.77 microg/g dust for B, p < 0.001). It also prevented the increase in serum levels of anti-Df IgE (2.5 U/ml for group A vs 0.7 U/ml for group B, p < 0.05) and positive reactions to skin prick testing with Df extract (63% for group A vs 31% for group B, p < 0.02) over 1 year. CONCLUSION: The bedding encasement with the mite-blocking fibers was effective for preventing atopic infants from being sensitized to HDMs, and it seems to be beneficial to modern busy housekeepers.

Allergens↗
PubMed1998

Assay for detecting IgE and IgG antibodies against Candida albicans cell-wall mannan.

In the present study, we assayed mannan-specific IgE and IgG antibodies in samples of serum isolated from blood collected from adult patients with bronchial asthma, using a liquid-phase method with a polysaccharide, mannan (Mn), purified from Candida albicans (C. alb), and investigated the relationships of allergenicity among a crude extract of C. alb, purified Mn, and acid protease (AP), The correlations between the titers of anti-Mn A and anti-Mn B IgE and IgG were very strong, and the levels of inhibition of anti-Mn A IgE and IgG reactions by Mn A and Mn B were almost identical. Although no common allergenicity was observed between Mn A and AP because there was no correlation between the titers of anti-Mn A and anti-AP IgE, and no inhibition of the anti-Mn A IgE reaction by AP, both antigens were found to exist in crude C. alb. The level of inhibition of anti-crude C. alb IgG reaction by Mn A or Mn B was about 60%. Approximately 70% inhibition of the anti-Mn A IgE reaction was observed for eight different fungal allergen extracts, but no inhibition was observed for 11 of the other fungal allergen extracts tested. The above results indicate that common antigenicity was observed between Mn A and Mn B in the human IgE and IgG antibody production system, and the cross-allergenicity observed among some fungi was considered to be the result of the common antigenicity of Mn isoforms.

Allergens↗
PubMed1998

Overproduction of DnaJ in Escherichia coli improves in vivo solubility of the recombinant fish-derived transglutaminase.

The overexpression of red sea bream (Pagrus major) transglutaminase (TGase, E.C. 2.3.2.13) in Escherichia coli mostly leads to the accumulation of biologically inactive enzyme. Although the solubility of the gene products could be improved by cultivation at a lower temperature (26-28 degrees C), most of the synthesized TGase was still in the form of insoluble aggregates. The effects of overproduction of molecular chaperones on the intracellular solubility of newly produced recombinant TGase were examined. The overexpression of dnaK or groES/EL did not improve solubility. However, DnaJ greatly increased the solubility of the recombinant TGase, resulting in active enzyme in the presence of calcium ions. Co-expression of dnaK along with dnaJ further increased the content of soluble TGase. Under our experimental conditions, supplementation with both DnaJ and DnaK elevated the TGase activity in the producer cells by roughly 4-fold, compared with the control strain cultured at 30 degrees C. Thus, we found that DnaJ is important in controlling the solubility of protein overproduced in E. coli.

Animals↗
PubMed1997

Epitope specificity of IgE antibodies to a major allergen (Cry j 1) of Japanese cedar pollen in sera of humans and monkeys with pollinosis.

Japanese cedar (Cryptomeria japonica) pollinosis has been reported to occur naturally in Japanese monkeys (Macaca fuscata) as well as humans. Using monoclonal antibodies (mAb) specific to Cry j 1, a major allergen in Japanese cedar pollen, we identified five independent epitopes (EP-1 to EP-5) on the molecule. The epitopes recognized by IgE antibodies in the sera of humans and monkeys with the pollinosis were analysed by an IgE enzyme-linked immunosorbent assay inhibition method with these mAb. In human patients, the mAb to EP-1 strongly blocked the binding of IgE antibodies in all patients' sera to Cry j 1. The reaction patterns of IgE antibodies in monkeys, however, varied among the troops of monkeys. In some troops, the mAb to EP-1 showed a blocking pattern similar to that for human patients. In other troops, mAb to EP-4 and EP-5 blocked binding of IgE. These results indicate that some, but not all, monkeys have antibody responses to the major allergen similar to those of humans.

Allergens↗
PubMed1997

Responses of monkeys with pollinosis to two major allergens of Japanese cedar pollen.

We examined the responses of two Japanese monkeys with pollinosis to two major allergens (Cry j 1 and Cry j 2) of Japanese cedar pollen. The two monkeys (A and B) had specific IgE antibodies to the allergens and showed a strong positive reaction to both of them in the intradermal test. In the histamine release test with peripheral blood mononuclear cells (PBMC), monkey A showed a typical pattern similar to that seen in human patients, while monkey B released a low level of histamine. The proliferative response of PBMC to both allergens in monkey A was weak, but was typical in monkey B. From clinical as well as immunological points of view, these monkeys may be a suitable animal model for Japanese cedar pollinosis in humans.

Allergens↗
PubMed1996

Measurement of airborne mite allergen exposure in individual subjects.

To evaluate the extent of personal exposure to airborne mite allergens, subjects were asked to carry a personal air sampler when in their houses. The level of Der 1 allergen trapped by the sampler was measured with a highly sensitive immunoassay. There were great variations in airborne Der 1 exposure in each subject. When used bedding was replaced with new allergen-free bedding, we detected a decrease in the allergen level. The use of new bedding seems to be an effective measure for reducing airborne mite allergen exposure.

Air Pollutants↗
PubMed1996

Seasonal changes in mite allergen (Der I and Der II) concentrations in Japanese homes.

BACKGROUND: There has been no report on seasonal changes in Der II allergen in floor and bedding dust. OBJECTIVE: The purpose of this study was to examine the extent of seasonal changes in Der I and Der II allergens in the floor and bedding dust found in houses. METHODS: We measured the absolute concentrations of mite allergens in dust collected monthly for 1 year from both the floors and bedding of eight houses in Tokyo. Dust samples were obtained from eight families without regard to their allergy histories. The concentrations of the Der p I, Der f I, and Der II allergens were measured by fluorometric sandwich ELISA. RESULTS: We found seasonal changes in the concentrations of these mite allergens. The highest concentrations of Der I (Der p I plus Der f I) and Der II (Der p II plus Der f II) were present from August to October, and the lowest ones from March to April. In floor dust, the mean highest concentrations of Der I and Der II (35.0 and 20.2 microgram of fine dust) were sevenfold and fivefold respectively, times the mean lowest concentrations. In bedding dust, the mean highest concentrations of Der I and Der II (51.3 and 29.6 microgram/g of fine dust) each were fourfold times the mean lowest concentrations. CONCLUSIONS: The patterns of seasonal changes in Der II in floor and bedding dust were similar to those of Der I.

Allergens↗
PubMed1996

Species-specific measurement of the second group of Dermatophagoides mite allergens, Der p 2 and Der f 2, using a monoclonal antibody-based ELISA.

BACKGROUND: The group 2 Dermatophagoides mite allergens, Der p 2 and Der f 2, were known to be highly crossreactive, and previous assays to measure Der p 2 and Der f 2 were not species-specific. OBJECTIVE: The aim of this study was to develop a monoclonal antibody-based ELISA (MoAb-ELISA) to species-specifically measure Der p 2 and Der f 2. METHODS: The MoAb-ELISA for Der p 2 and Der f 2 was performed using species-specific MoAbs for Der p 2 and Der f 2 and a biotinylated second MoAb which recognized a common epitope on both Der p 2 and Der f 2. RESULTS: The assay was highly species-specific, reproducible and sensitive. Thirty-two house dust samples were assayed by the MoAb-ELISA for Der p 2 and Der f 2 and by a previously reported radioimmunoassay for Der 2 with rabbit anti-Der 2 antibodies. The summed values for Der p 2 and Der f 2 by the MoAb-ELISA demonstrated a good correlation with the Der 2 values using the radioimmunoassay (r = 0.978). Furthermore, the proportion of the Der p 2 level in the total Der 2 level (Der p 2 divided by Der p 2 plus Der f 2) correlated well with that of the D. pteronyssinus mite number to the total Dermatophagoides mite number identified by species (r = 0.970). CONCLUSION: The MoAb-ELISA for Der p 2 and Der f 2, as well as that of Der p 1 and Der f 1, will be useful for the standardization of mite extracts and for the assessments of mite allergen exposure.

Animals↗
PubMed1996

Allergenicity of acid protease secreted by Candida albicans.

We have previously reported the cases of Candida albicans (C. alb) acid protease (CAAP)-induced atopic asthma. In this study, the allergenicity of the released enzyme CAAP was examined among asthmatic patients with positive immediate skin response to crude C. alb antigen. Among 49 patients with positive skin response to crude C. alb, anti-crude C. alb IgE antibodies were detected in 40 and anti-CAAP IgE antibodies were detected in 18. Moreover, anticrude C. alb IgE antibodies were detected in all of the patients in whom anti-CAAP IgE antibodies were detected. No correlations between IgG antibodies to both antigens or between IgE and IgG antibodies to CAAP were observed. CAAP induced significant T-cell proliferation in 20/28 patients showing positive T-cell proliferation response to crude C. alb antigen. Most of the patients showing positive conjunctival response to crude C. alb antigen also showed positive response to CAAP. Most of the patients showing high levels of serum IgE antibody and positive histamine-release response of peripheral blood leukocytes to CAAP showed positive conjunctival response. The results indicate that CAAP is an important allergen in C. alb-related mucosal allergy.

Allergens↗
PubMed1996

Epitope analysis of HLA-DR-restricted helper T-cell responses to Der p II, a major allergen molecule of Dermatophagoides pteronyssinus.

T-cell epitopes of Der p II, a major allergen of Dermatophagoides pteronyssinus, were analyzed by using human T-cell clones. We tested 38 cloned T cells from two Japanese patients with allergic rhinitis, and identified at least two peptides (K33-T47 and I58-C73) as helper T-cell epitopes. The former epitope was shown to be restricted by HLA-DRB1*1502, and the latter by HLA-DRB1*0405, both of which are typical Japanese HLA-DR alleles, suggesting that those T-cell epitopes might be important for the onset of house-dust mite allergy in the Japanese population. We prepared 15 analog peptides of the HLA- DRB1*1502-restricted 15-mer peptide. Of those 15 residues, five (F35, L37, A39, F41, and E42) were critical for the epitope activity, and three residues (F35, A39, and E42) seemed to be included in anchor motifs for HLA-DRB1*1502. The epitope peptide was also recognized by HLA-DRB1*1502-positive healthy donors; however, only allergic T cells showed Th2 functions. Antigen-presenting cells of nonallergic donors were able to activate allergic T cells to express Th2 function. This seemed to suggest that antigen recognition of T cells, as well as additional unknown factors which promote Th2, rather than Th1, responses, might be important for the onset of house-dust mite allergy.

Allergens↗
PubMed1996

Cloning and sequence analysis of a cDNA encoding salmon (Onchorhynchus keta) liver transglutaminase.

We isolated cDNA clones encoding a transglutaminase (TGase: EC 2.3.2.13) from a salmon (Onchorhynchus keta) cDNA library prepared from the liver. In the cDNA sequence combined, an open reading frame coding for a protein of 680 aa was found. The deduced sequence showed a considerable similarity (62.4%) to that of red sea bream TGase. By comparison of sequence similarity to other TGases, the structure of salmon TGase was like tissue type TGases, rather than membrane-associated type or plasma type TGases. As a structural feature of salmon TGase, 3 aa residues were substituted in the 25 aa sequence around the active site Cys residue, which is conserved among several tissue type TGases. The critical residues thought to form the catalytic-center triad (Cys272, His331, and Asp301) were found in the highly conserved region, but the region surrounding Tyr511, which corresponds to the residue participates in hydrogen-bond interactions of active center domain, was less similar to other TGases, except for red sea bream TGase. These finding suggests that the overall structure of fish TGase resembles tissue-type TGases, but has some unique structure.

Amino Acid Sequence↗
PubMed1996

Major Dermatophagoides mite allergen, Der 1, in soft toys.

BACKGROUND: Allergen avoidance is recommended when treating atopic asthma. OBJECTIVES: Soft toys are often kept in close proximity to children and may serve as a source of exposure. Due to the potential danger from the mite allergen content of these toys, Der 1 from toys was measured. METHODS: We quantified the level of Der 1 (Der p 1 + Der f 1) in both 30 new and 174 old soft toys (weight 216 +/- 2.5 g, height 26.5 +/- 3.4 cm), as well as in washed and in vacuumed soft toys. Dust was collected using an electric vacuum cleaner. Der 1 was measured by monoclonal antibody-based enzyme-linked immunosorbent assay (MoAb-ELISA). RESULTS: In brand new toys Der 1 was 0.1 microgram/g of dust, and in toys used for 1 year, 9.0; 2 year, 22.2; 3 year, 18.9; and more than 4 year, 22.7 micrograms/g of dust. Der 1 in new toys was measured every 4 months for 1 year. Der 1 rapidly increased 10- to 20-fold in the first 4 months, but there was no clear seasonal change. In toys washed using a chemical detergent or cleaned using a vacuum cleaner, there was a stastistically significant (P < 0.001) decrease in Der 1 in the washed group, but not in the vacuumed group. CONCLUSION: These results confirm that mite allergens accumulate rapidly in toys to form a potentially important source of allergens and that washing toys with a chemical detergent is effective in the reduction of allergens.

Allergens↗
PubMed1996

Antigenic analysis of Cryptomeria japonica and Chamaecyparis obtusa using anti-Cry j 1 monoclonal antibodies.

In Japan, pollen of Cryptomeria japonica and Chamaecyparis obtusa are a yearly source of distress for many people suffering seasonally from allergic rhinitis. To study common epitopes shared by the two species, two monoclonal antibodies (moAbs) were raised against Cry j 1, which is the most predominant allergen in C. japonica. One of the moAbs was found to be reactive even to the major allergen of C. obtusa, demonstrating that the moAb (J1B01) can detect an epitope shared by both species J1B01 strongly inhibited the binding of the major allergens of C. japonica and C. obtusa to IgE of patients who are sensitive to C. japonica and C. obtusa. This finding signifies the importance of the epitope recognized by J1B01.

Allergens↗
PubMed1995

Tissue-type transglutaminase from red sea bream (Pagrus major). Sequence analysis of the cDNA and functional expression in Escherichia coli.

A cDNA clone encoding a tissue-type transglutaminase (TGase) was isolated from a cDNA library prepared from the liver of red sea bream (Pagrus major). The cDNA sequence had an open reading frame coding for a protein of 695 amino acids and showed 43% identity to the sequence of guinea pig liver TGase, revealing a relatively low overall similarity. However, the 25-amino-acid sequence containing the putative active site (Cys272) of the enzyme was completely conserved between the two species, and was also identical to the corresponding regions of human and bovine endothelial cell TGases. In addition, the critical residues (His332 and Asp355) thought to form the catalytic-center triad together with Cys272, were found in the highly conserved region. The red sea bream TGase had an extension of 11 amino acids in the C-terminal region and some differences in the N-terminal region when compared with guinea pig TGase. From the cloned cDNA, a semi-synthetic TGase gene suitable for overexpression in Escherichia coli was constructed (pTTG2-22). At a reduced temperature (28 degrees C), E. coli cells transformed with pTTG2-22 could produce soluble TGase which exhibited catalytic activity in the presence of calcium. E. coli extracts containing the recombinant red sea bream TGase induced gelation of actomyosin solutions, accompanied by a significant increase of epsilon-(gamma-glutamyl)lysine bonds, which are predominantly derived from the cross-linking of myosin heavy chains. These results indicate that this fish TGase should be useful for further analysis of TGase structure/function relationships and that it could also be employed to enhance the viscoelastic properties of proteinaceous materials.

Actomyosin↗