Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 144
Filter
1.
Benef Microbes ; 14(6): 623-640, 2023 Nov 29.
Article in English | MEDLINE | ID: mdl-38350466

ABSTRACT

We evaluated the benefits of heat-stable carotenoid-producing Bacillus marisflavi SH8 spores individually and in combination with non-pigmented Bacillus subtilis SH23 spores on growth, colour change, nutritional content, innate immunity, and gut microbiota of white-leg shrimp. White-leg shrimp (Litopenaeus vannamei; n = 30 per tank; 2 tanks per group) were provided feed without (control group) or with SH8, SH23, or mixed spores (total, 1 × 106 cfu/g pellet) for 28 d. The SH8 and SH8-23 combination groups had significantly higher specific growth rates (9.6 and 11.0%), improved red-colour score (4 scores), astaxanthin concentration (1.8- and 2.3-fold), lipid contents (30 and 50%), and superoxidase dismutase activity (8.5 and 12.3%) than that of the control group. Analysis of shrimp's gut microbiome using 16S rRNA metagenome sequencing revealed increased abundance of four useful species and reduced abundance of four harmful species in the combination group than in the control group. Heat-stable Bacillus spore combination improved growth parameters, nutrient content, red-colour score, live counts, and abundance of useful bacteria in the gut of L. vannamei. This is the first study to show the benefits of combining highly heat-stable pigmented and non-pigmented Bacillus spores and their possible mechanisms in a shrimp model.


Subject(s)
Bacillus , Gastrointestinal Microbiome , Penaeidae , Probiotics , Animals , Bacillus subtilis , Hot Temperature , RNA, Ribosomal, 16S/genetics , Spores, Bacterial , Probiotics/analysis , Carotenoids , Penaeidae/genetics , Penaeidae/microbiology , Immunity, Innate , Animal Feed/analysis , Diet
2.
J Appl Microbiol ; 129(1): 51-62, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32027769

ABSTRACT

AIMS: We investigated the potential cooperative effects of carotenoid-producing Bacillus aquimaris SH6 and nonpigmented Bacillus subtilis SH23 on white-leg shrimp growth and health. METHODS AND RESULTS: SH6, SH23 and a combination of both spores (1 × 106  CFU per g pellet) were administered in shrimp. The growth rate (2·36% day-1 ), red-colour score (25) and astaxanthin concentration (3·5 µg g-1 shrimp) were maximum in two-spore-administered shrimp. Immune-related Rho mRNA expression level and phenoloxidase and superoxidase dismutase activities were higher in two-spore-administered shrimp than in control shrimp, with Rho mRNA expression level being 55-fold higher in two-spore-administered shrimp than in SH6-administered shrimp and phenoloxidase activity being 1·2-fold higher in two-spore-administered shrimp than in SH23-administered shrimp. Although live SH6 count was 2·7-fold lower, SH6 germination level was 3·5-fold higher in the combination group than in SH6 group. CONCLUSIONS: When both SH6 and SH23 spores were administered, SH6 spore germination was enhanced and cooperative improvement was seen in growth, astaxanthin level and red-colour score of white-leg shrimp; however, immune-related parameters were induced in a noncooperative manner. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report showing the cooperative probiotic activities of Bacillus strains and their possible mechanisms in a shrimp model.


Subject(s)
Bacillus/physiology , Gastrointestinal Microbiome , Penaeidae/chemistry , Penaeidae/growth & development , Probiotics , Animals , Bacillus/metabolism , Carotenoids/metabolism , Penaeidae/microbiology , Pigmentation , Shellfish/analysis , Shellfish/microbiology , Spores, Bacterial/metabolism , Spores, Bacterial/physiology , Xanthophylls/analysis
7.
Blood Cancer J ; 2(5): e72, 2012 May.
Article in English | MEDLINE | ID: mdl-22829974

ABSTRACT

We investigated prognostic factors for the clinical outcome of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) following imatinib-based therapy. Among 100 adult patients who were prospectively enrolled in the JALSG Ph+ALL202 study, 97 patients obtained complete remission (CR) by imatinib-combined chemotherapy, among whom 60 underwent allo-HSCT in their first CR. The probabilities of overall survival (OS) and disease-free survival (DFS) at 3 years after HSCT were 64% (95% CI, 49-76) and 58% (95% CI, 43-70), respectively. Prognostic factor analysis revealed that the major BCR-ABL transcript was the only unfavorable predictor for OS and DFS after HSCT by both univariate (HR, 3.67 (95% CI 1.49-9.08); P=0.005 and HR, 6.25 (95% CI, 1.88-20.8); P=0.003, respectively) and multivariate analyses (HR, 3.20 (95% CI, 1.21-8.50); P=0.019 and HR, 6.92 (95% CI, 2.09-22.9); P=0.002, respectively). Minimal residual disease status at the time of HSCT had a significant influence on relapse rate (P=0.015). Further study of the BCR-ABL subtype for the clinical impact on outcome of allo-HSCT in Ph+ALL is warranted.

8.
Transplant Proc ; 42(10): 4127-31, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21168643

ABSTRACT

OBJECTIVES: To describe our experience with 126 consecutive living-donor liver transplantation (LDLT) procedures performed because of biliary atresia and to evaluate the optimal timing of the operation. PATIENTS AND METHODS: Between May 2001 and January 2010,126 patients with biliary atresia underwent 130 LDLT procedures. Mean (SD) patient age was 3.3 (4.2) years, and body weight was 13.8 (10.7) kg. Donors included 64 fathers, 63 mothers, and 3 other individuals. The left lateral segment was the most commonly used graft (75%). Patients were divided into 3 groups according to body weight: group 1, less than 8 kg (n = 40); group 2,8 to 20 kg (n = 63); and group 3, more than 20 kg (n = 23). Medical records were reviewed retrospectively. Follow up was 4.5 (2.7) years. RESULTS: All group 3 donors underwent left lobectomy, and all group 1 donors underwent left lateral segmentectomy. No donors required a second operation or died. Comparison of the 3 groups demonstrated that recipient Pediatric End-Stage Liver Disease score in group 1 was highest, operative blood loss in group 2 was lowest (78 mL/kg), and operative time in group 3 was longest (1201 minutes). Hepatic artery complications occurred more frequently in group 1 (17.9%), and biliary stenosis (43.5%) and gastrointestinal perforation (8.7%) occurred more frequently in group 3. The overall patient survival rates at 1, 5, and 9 years was 98%, 97%, and 97%, respectively. Five-year patient survival rate in groups 1,2, and 3 were 92.5%, 100%, and 95.7%, respectively. Gastrointestinal perforation (n = 2) was the primary cause of death. CONCLUSIONS: Living-donor liver transplantation is an effective treatment of biliary atresia, with good long-term outcome. It seems that the most suitable time to perform LDLT to treat biliary atresia is when the patient weighs 8 to 20 kg.


Subject(s)
Biliary Atresia/surgery , Liver Transplantation , Living Donors , Adult , Female , Humans , Immunosuppressive Agents/administration & dosage , Male , Middle Aged
9.
Bone Marrow Transplant ; 41(12): 1029-35, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18332910

ABSTRACT

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) has proven effective in adult T-cell leukemia/lymphoma (ATL) patients. To study the graft-versus-ATL (Gv-ATL) effects after allo-HSCT, we analyzed 21 ATL patients who had been treated at our hospital. Of these, 18 had acute-, 2 had lymphoma- and 1 had chronic-type ATL; at allo-HSCT, seven patients were in CR, one was in PR, five had stable disease (SD) and eight had progressive disease (PD). Disease state after allo-HSCT was CR in 14, PR in 3, SD in 1 and PD in 3 patients. Among 15 patients who survived longer than 100 days, ATL relapsed in 10 patients, skin relapsed in 9 patients and 5 had relapsed on the skin alone. After we discontinued immunosuppressant therapy in these 10 patients, 8 manifested GVHD; ATL was ameliorated to CR in 6 patients. Donor lymphocytes were infused into two patients who did not show GVHD; one obtained CR. In five patients with skin relapse alone, four patients achieved CR following the discontinuation of the immunosuppressants. Our results demonstrate that relapse of ATL after allo-HSCT tends to develop on skin, and Gv-ATL effects played a critical role in the outcome of allo-HSCT for ATL.


Subject(s)
Graft vs Leukemia Effect , Hematopoietic Stem Cell Transplantation/methods , Leukemia-Lymphoma, Adult T-Cell/therapy , Adult , Cohort Studies , Disease-Free Survival , Drug Administration Schedule , Female , Graft vs Host Disease/drug therapy , Humans , Immunosuppressive Agents/administration & dosage , Immunosuppressive Agents/adverse effects , Kaplan-Meier Estimate , Leukemia-Lymphoma, Adult T-Cell/pathology , Male , Middle Aged , Recurrence , Retrospective Studies , Skin Diseases/pathology , Transplantation, Homologous
10.
Biomed Pharmacother ; 59 Suppl 2: S323-4, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16507401

ABSTRACT

This study has been initiated to evaluate the safety, clinical and pathologic response as well as the relation of response (pCR or non-pCR) and survival (overall and relapse-free) of fluorouracil, epirubicin and cyclophosphamide (FEC) followed by docetaxel (DOC) as preoperative chemotherapy in patients with operable breast cancer. Japanese patients with primary breast cancer, Tlc-3N0M0 or T1-3NIM0, age 20-60, PS 0-1 were included in this study. Preoperative chemotherapy consisted of 4 cycles of FEC (500 mg/m(2), 100 mg/m(2), 500 mg/m(2)) every 3 weeks followed by 4 cycles of DOC (75 mg/m(2)) every 3 weeks. Since June 2002, 200 patients were enrolled in this study, and the time of this interim analysis, 80 patients were evaluable for safety and clinical efficacy. The overall clinical response rate was 71.4% (14% CR, 44% PR, 42% SD/PD), and the only G3,4 toxicities, neutropenia and febrile neutropenia were observed in 54% and 14% of patients, respectively. Eighty nine patients were evaluable for pathologic response by central review. Pathologic response was evaluated among invasive tumors on multiple cross-section specimens based on a modified version of the Japanese grading system for Japanese Breast Cancer Society. The pathologic response rate was 17%. In this ongoing trial, FEC followed by DOC was active and well tolerated.


Subject(s)
Antineoplastic Agents, Phytogenic/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/drug therapy , Taxoids/therapeutic use , Antineoplastic Agents, Phytogenic/adverse effects , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Breast Neoplasms/pathology , Breast Neoplasms/surgery , Chemotherapy, Adjuvant , Combined Modality Therapy , Cyclophosphamide/adverse effects , Cyclophosphamide/therapeutic use , Docetaxel , Endpoint Determination , Epirubicin/adverse effects , Epirubicin/therapeutic use , Female , Fluorouracil/adverse effects , Fluorouracil/therapeutic use , Humans , Survival , Taxoids/adverse effects
11.
Bone Marrow Transplant ; 34(10): 897-9, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15361902

ABSTRACT

With the recent progress in reduced-intensity conditioning stem cell transplantation (RIST) and taking into consideration the concept of feto-maternal immunological tolerance, we carried out non-T-cell depleted HLA haploidentical RIST from noninherited maternal antigen (NIMA) complementary siblings or offspring donors for four older patients: a patient with myeloplastic syndrome (MDS) and three patients with adult T-cell leukemia (ATL) in partial remission or with progressive disease. All patients showed early, durable engraftment, and no serious toxicities were observed apart from grade III mucositis in one case. Grade II acute GVHD occurred in two cases, which was well-controlled. In one ATL patient whose donor did not have NIMA microchimerism, tacrolimus could not be continued after engraftment due to renal dysfunction, and grade III acute GVHD (gut: stage 4) occurred on day 35. A patient with MDS was free from disease (requiring no transfusions and with a normal bone marrow) for 15 months. Two cases of ATL relapsed. Feto-maternal tolerance may lead to new RIST strategies in the haploidentical reduced-intensity situation, but further evaluation is required.


Subject(s)
Hematopoietic Stem Cell Transplantation/methods , Histocompatibility Testing , Transplantation Conditioning/methods , Transplantation Tolerance/immunology , Age Factors , Family , Female , Graft vs Host Disease , Haplotypes , Hematopoietic Stem Cell Transplantation/adverse effects , Humans , Leukemia, T-Cell/therapy , Male , Middle Aged , Myelodysplastic Syndromes/complications , Myelodysplastic Syndromes/therapy , Tissue Donors , Transplantation Chimera , Treatment Outcome
13.
Eur J Surg Oncol ; 29(10): 845-8, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14624775

ABSTRACT

AIMS: Accurate evaluation of sentinel nodes is of clinical importance to avoid further surgery for axillary node dissection. A prospective study was carried out to investigate the feasibility and accuracy of touch imprint cytology (TIC) and touch imprint immunohistochemistry (TIHC). METHODS: Two hundred and five sentinel nodes from consecutive 118 patients with primary breast cancer were studied after successful identification of sentinel nodes. Sentinel nodes were sectioned at 2 mm intervals and imprint specimens prepared from all cut surfaces were subjected to Papanicolaou staining and immunohistochemical staining using anti-cytokeratin antibody. RESULTS: Forty-nine sentinel nodes from 40 patients were positive by permanent section. The sensitivity of TIC was 84% (41/49) per sentinel node and 83% (33/40) on a per patient basis. The sensitivity of TIHC was 86% (42/49) per sentinel node and 83% (33/40) on a per patient basis. When the results of TIC and TIHC were combined, the sensitivity was 88% (43/49) per sentinel node and 85% (34/40) on a per patient basis. Among the 156 negative sentinel nodes, four sentinel nodes from four different patients were consistently positive by TIC and TIHC, but only one patient out of 78 node-negative patients was upstaged. CONCLUSIONS: Touch imprint cytology is sufficiently sensitive for intraoperative evaluation of sentinel nodes. A slight improvement in the sensitivity is expected when immunohistochemistry is used. The combination of these methods provides better sensitivity than either method alone.


Subject(s)
Breast Neoplasms/pathology , Sentinel Lymph Node Biopsy/methods , Adult , Aged , Aged, 80 and over , Cytodiagnosis/methods , Female , Humans , Immunohistochemistry , Intraoperative Period , Lymphatic Metastasis/diagnosis , Middle Aged , Prospective Studies , Sensitivity and Specificity
14.
Ann Oncol ; 14(1): 62-70, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12488294

ABSTRACT

BACKGROUND: To compare the efficacy, safety and tolerability of letrozole, an advanced non-steroidal aromatase inhibitor, and fadrozole hydrochloride, an older-generation drug in this class, we conducted a randomised double-blind trial in postmenopausal women with advanced breast cancer. PATIENTS AND METHODS: One hundred and fifty-seven postmenopausal women with advanced breast cancer were enrolled and randomly assigned to receive letrozole or fadrozole in a multicentre, randomised double-blind trial in Japan. One hundred and fifty-four eligible patients were treated with either letrozole 1.0 mg once daily (n = 77) or fadrozole 1.0 mg twice daily (n = 77), for a minimum of 8 weeks. RESULTS: Letrozole showed a significantly higher overall objective response rate [complete response (CR) + partial response (PR)] than fadrozole (31.2% and 13.0%, respectively; P = 0.011, Fisher's exact test). Clinical benefits defined as CR, PR and stable disease (no change in status for more than 24 weeks) were also higher in patients treated with letrozole (50.6%) than fadrozole (35.1%). Letrozole was significantly superior to fadrozole in terms of the dominant lesion in soft tissue, bone and viscera (P = 0.011, stratified Mantel-Haenszel test). Median time to progression was 211 days in the letrozole group and 113 days in the fadrozole group with no significant difference (P = 0.175, log-rank test). Letrozole markedly reduced the estradiol, estrone and estrone sulfate levels in peripheral blood within 4 weeks. The suppressive effect of fadrozole on these hormone levels was insufficient. Adverse drug reactions were observed in 35.9% of the patients treated with letrozole and in 39.5% of those treated with fadrozole with no significant difference between the two groups (P = 0.74, Fisher's exact test). Most of the adverse drug reactions were rated as grade 1 or 2. CONCLUSIONS: The results show letrozole at a dose of 1.0 mg once daily to be more effective in treating postmenopausal women with advanced breast cancer than fadrozole at 1.0 mg twice daily, with similar safety and tolerability profiles.


Subject(s)
Antineoplastic Agents/therapeutic use , Aromatase Inhibitors , Breast Neoplasms/drug therapy , Enzyme Inhibitors/therapeutic use , Estrone/analogs & derivatives , Fadrozole/therapeutic use , Neoplasm Recurrence, Local/drug therapy , Nitriles/therapeutic use , Triazoles/therapeutic use , Administration, Oral , Antineoplastic Agents/adverse effects , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Disease Progression , Double-Blind Method , Enzyme Inhibitors/adverse effects , Estradiol/blood , Estrone/blood , Fadrozole/adverse effects , Female , Humans , Letrozole , Middle Aged , Neoplasm Recurrence, Local/metabolism , Neoplasm Recurrence, Local/pathology , Nitriles/adverse effects , Postmenopause , Receptors, Estrogen/metabolism , Receptors, Progesterone/metabolism , Safety , Survival Rate , Triazoles/adverse effects
15.
Haematologia (Budap) ; 31(4): 369-72, 2002.
Article in English | MEDLINE | ID: mdl-12038522

ABSTRACT

A 51-year-old male who had intractable leg ulcers during treatment for chronic myelogenous leukaemia with hydroxyurea (HU) is reported. His leg ulcers were treated by application of tretinoin tocoferil (TT) ointment after surgical debridement; good results were obtained. Although stopping HU administration is vitally important, surgical debridement and TT application are effective for treating leg ulcers due to HU.


Subject(s)
Antineoplastic Agents/adverse effects , Hydroxyurea/adverse effects , Leg Ulcer/chemically induced , Leg Ulcer/therapy , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Tretinoin/analogs & derivatives , Vitamin E/analogs & derivatives , Antineoplastic Agents/therapeutic use , Debridement , Drug Combinations , Humans , Hydroxyurea/therapeutic use , Leg Ulcer/pathology , Male , Middle Aged , Ointments , Tretinoin/administration & dosage , Tretinoin/therapeutic use , Vitamin E/administration & dosage , Vitamin E/therapeutic use
16.
Ann Oncol ; 13(2): 286-92, 2002 Feb.
Article in English | MEDLINE | ID: mdl-11886007

ABSTRACT

BACKGROUND: This study was conducted to investigate the efficacy and toxicity of weekly docetaxel administration in patients with metastatic breast cancer. PATIENTS AND METHODS: Thirty-seven women were treated with 1 h infusions of docetaxel at 40 mg/m2/week after pre-medication with 8 mg dexamethazone. Each cycle consisted of three consecutive weekly treatments followed by a 1 week rest. All patients were assessed for toxicity; five patients were not assessable for clinical response, time to progression (TTP) and overall survival (OS) because of early treatment failure, but they were included in intention-to-treat analysis. RESULTS: Patients received a median of four cycles (range, 1-9), with a median dose intensity of 28 mg/m2/week (range 22-30) and a median relative dose intensity of 0.95 (range 0.73-1.0). No patients showed complete response, whereas 14 had partial response, which accounted for 38% of objective response rate [95% confidence interval (CI) 22% to 53%]. In addition, three patients (8%, 95% CI 0% to 17%) had stable disease over 6 months. Clinical responses were achieved at a median of three cycles (range 1-4 cycles). The median TTP and OS were 5 and 12 months, respectively. The weekly docetaxel regimen was generally well tolerated. About half of the patients experienced grade > or = 1 neutropenia; only 19% had grade 3/4 neutropenia, including one case of grade 4. No febrile neutropenia was observed and fluid retention syndrome was uncommon. Non-hematologic toxicity, however, such as asthenia/fatigue, nail damage, tearing or hearing disorders, was seen with successive treatment cycles. CONCLUSIONS: Weekly docetaxel at 40 mg/m2/week is an active and feasible regimen for patients with metastatic breast cancer.


Subject(s)
Antineoplastic Agents, Phytogenic/therapeutic use , Breast Neoplasms/drug therapy , Paclitaxel/analogs & derivatives , Paclitaxel/therapeutic use , Taxoids , Adult , Aged , Docetaxel , Female , Humans , Middle Aged , Neoplasm Metastasis , Paclitaxel/adverse effects , Treatment Outcome
17.
Bone Marrow Transplant ; 27(1): 15-20, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11244433

ABSTRACT

Adult T cell leukemia/lymphoma (ATL) is a poor prognosis T cell malignancy. In order to improve the outcome, we employed allogeneic stem cell transplantation (allo-SCT) for ATL in 10 patients, nine of whom were from HLA-identical siblings and one from an unrelated donor. Conditioning regimens varied among the patients except that all received total body irradiation. The patients tolerated the regimens well with mild, if any toxicity, and engraftment occurred in all cases. Median leukemia-free survival after allo-SCT was 17.5+ months (range 3.7-34.4+). Six of the 10 patients developed acute GVHD (one case each with grade I, III or IV, and three cases with grade II) and three patients developed extensive chronic GVHD. Four patients died after allo-SCT during the study period from either acute GVHD (grade IV), pneumonitis, gastrointestinal bleeding or renal insufficiency. Two of the 10 cases with no symptoms of GVHD relapsed with clinical ATL. These results strongly suggest that allo-SCT may improve the survival in ATL if a controlled degree of GVHD develops.


Subject(s)
Hematopoietic Stem Cell Transplantation/standards , Leukemia-Lymphoma, Adult T-Cell/surgery , Lymphoma, T-Cell/surgery , Adult , Cause of Death , DNA, Viral/blood , Disease-Free Survival , Female , Graft vs Host Disease , Hematopoietic Stem Cell Transplantation/adverse effects , Hematopoietic Stem Cell Transplantation/mortality , Human T-lymphotropic virus 1/drug effects , Human T-lymphotropic virus 1/genetics , Humans , Japan , Leukemia-Lymphoma, Adult T-Cell/virology , Lymphoma, T-Cell/virology , Male , Middle Aged , Survival Rate , Transplantation Conditioning/adverse effects , Transplantation Conditioning/methods , Transplantation Conditioning/standards , Transplantation, Homologous , Treatment Outcome
18.
Breast Cancer ; 7(4): 281-3, 2000.
Article in English | MEDLINE | ID: mdl-11114850

ABSTRACT

BACKGROUND: Although most surgeons perform some form of axillary lymph node dissection (ALND) as part of locoregional management of operable breast cancer, the extent of dissection remains controversial. PATIENTS AND METHODS: Observation of the axilla trial (protocol I) and partial dissection trial (protocol I) began in January 1996. Between January 1996 and May 2000, 45 post-menopausal and 207 women with clinically node-negative breast cancer were enrolled into protocol I and protocol II respectively. RESULTS: The 4-year cumulative incidence rate of axillary recurrence was 7% in patients with untreated the axilla. The 4-year overall survival rate was 98% in patients with untreated the axilla. The 4-year disease-free and overall survival rates were 96% and 98% respectively in patients treated with partial dissection. CONCLUSION: Total axillary dissection seems to be unnecessary in Japanese breast cancer patients with relatively small tumors.


Subject(s)
Breast Neoplasms/surgery , Lymph Node Excision , Adult , Aged , Aged, 80 and over , Axilla , Female , Humans , Middle Aged
20.
J Bacteriol ; 182(23): 6732-41, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11073919

ABSTRACT

Lysine decarboxylase (LDC; EC 4.1.1.18) from Selenomonas ruminantium comprises two identical monomeric subunits of 43 kDa and has decarboxylating activities toward both L-lysine and L-ornithine with similar K(m) and V(max) values (Y. Takatsuka, M. Onoda, T. Sugiyama, K. Muramoto, T. Tomita, and Y. Kamio, Biosci. Biotechnol. Biochem. 62:1063-1069, 1999). Here, the LDC-encoding gene (ldc) of this bacterium was cloned and characterized. DNA sequencing analysis revealed that the amino acid sequence of S. ruminantium LDC is 35% identical to those of eukaryotic ornithine decarboxylases (ODCs; EC 4.1.1.17), including the mouse, Saccharomyces cerevisiae, Neurospora crassa, Trypanosoma brucei, and Caenorhabditis elegans enzymes. In addition, 26 amino acid residues, K69, D88, E94, D134, R154, K169, H197, D233, G235, G236, G237, F238, E274, G276, R277, Y278, K294, Y323, Y331, D332, C360, D361, D364, G387, Y389, and F397 (mouse ODC numbering), all of which are implicated in the formation of the pyridoxal phosphate-binding domain and the substrate-binding domain and in dimer stabilization with the eukaryotic ODCs, were also conserved in S. ruminantium LDC. Computer analysis of the putative secondary structure of S. ruminantium LDC showed that it is approximately 70% identical to that of mouse ODC. We identified five amino acid residues, A44, G45, V46, P54, and S322, within the LDC catalytic domain that confer decarboxylase activities toward both L-lysine and L-ornithine with a substrate specificity ratio of 0.83 (defined as the k(cat)/K(m) ratio obtained with L-ornithine relative to that obtained with L-lysine). We have succeeded in converting S. ruminantium LDC to form with a substrate specificity ratio of 58 (70 times that of wild-type LDC) by constructing a mutant protein, A44V/G45T/V46P/P54D/S322A. In this study, we also showed that G350 is a crucial residue for stabilization of the dimer in S. ruminantium LDC.


Subject(s)
Carboxy-Lyases/genetics , Evolution, Molecular , Genes, Bacterial , Ornithine Decarboxylase/genetics , Selenomonas/enzymology , Amino Acid Sequence , Animals , Base Sequence , Binding Sites , Carboxy-Lyases/chemistry , Carboxy-Lyases/classification , Carboxy-Lyases/metabolism , Cloning, Molecular , DNA, Bacterial , Lysine/metabolism , Mice , Molecular Sequence Data , Ornithine/metabolism , Ornithine Decarboxylase/classification , Ornithine Decarboxylase/metabolism , Protein Conformation , Selenomonas/genetics , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Substrate Specificity , Transcription, Genetic
SELECTION OF CITATIONS
SEARCH DETAIL
...