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Biomedical subjects

M Takano

Publications and source records attributed to M Takano.

At least 109 records · Page 6Linked to original sources
PubMed1999

The bglA gene of Aspergillus kawachii encodes both extracellular and cell wall-bound beta-glucosidases.

We cloned the genomic DNA and cDNA of bglA, which encodes beta-glucosidase in Aspergillus kawachii, based on a partial amino acid sequence of purified cell wall-bound beta-glucosidase CB-1. The nucleotide sequence of the cloned bglA gene revealed a 2,933-bp open reading frame with six introns that encodes an 860-amino-acid protein. Based on the deduced amino acid sequence, we concluded that the bglA gene encodes cell wall-bound beta-glucosidase CB-1. The amino acid sequence exhibited high levels of homology with the amino acid sequences of fungal beta-glucosidases classified in subfamily B. We expressed the bglA cDNA in Saccharomyces cerevisiae and detected the recombinant beta-glucosidase in the periplasm fraction of the recombinant yeast. A. kawachii can produce two extracellular beta-glucosidases (EX-1 and EX-2) in addition to the cell wall-bound beta-glucosidase. A. kawachii in which the bglA gene was disrupted produced none of the three beta-glucosidases, as determined by enzyme assays and a Western blot analysis. Thus, we concluded that the bglA gene encodes both extracellular and cell wall-bound beta-glucosidases in A. kawachii.

Amino Acid Sequence↗
PubMed1999

Characterization of biosynthetic enzymes for ectoine as a compatible solute in a moderately halophilic eubacterium, Halomonas elongata.

1,4,5,6-Tetrahydro-2-methyl-4-pyrimidinecarboxylic acid (ectoine) is an excellent osmoprotectant. The biosynthetic pathway of ectoine from aspartic beta-semialdehyde (ASA), in Halomonas elongata, was elucidated by purification and characterization of each enzyme involved. 2,4-Diaminobutyrate (DABA) aminotransferase catalyzed reversively the first step of the pathway, conversion of ASA to DABA by transamination with L-glutamate. This enzyme required pyridoxal 5'-phosphate and potassium ions for its activity and stability. The gel filtration estimated an apparent molecular mass of 260 kDa, whereas molecular mass measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was 44 kDa. This enzyme exhibited an optimum pH of 8.6 and an optimum temperature of 25 degreesC and had Kms of 9.1 mM for L-glutamate and 4.5 mM for DL-ASA. DABA acetyltransferase catalyzed acetylation of DABA to gamma-N-acetyl-alpha,gamma-diaminobutyric acid (ADABA) with acetyl coenzyme A and exhibited an optimum pH of 8.2 and an optimum temperature of 20 degreesC in the presence of 0.4 M NaCl. The molecular mass was 45 kDa by gel filtration. Ectoine synthase catalyzed circularization of ADABA to ectoine and exhibited an optimum pH of 8.5 to 9.0 and an optimum temperature of 15 degreesC in the presence of 0.5 M NaCl. This enzyme had an apparent molecular mass of 19 kDa by SDS-PAGE and a Km of 8.4 mM in the presence of 0. 77 M NaCl. DABA acetyltransferase and ectoine synthase were stabilized in the presence of NaCl (>2 M) and DABA (100 mM) at temperatures below 30 degreesC.

Acetyltransferases↗
PubMed1999

Preoperative determination of several serum tumor markers in patients with primary epithelial ovarian carcinoma.

This study was designed to evaluate the clinical significance of the use of preoperative serum tumor markers in primary epithelial ovarian cancer. Subjects comprised 111 patients with primary epithelial ovarian cancer. Lactate dehydrogenase (LDH), alpha-hydroxybutyrate dehydrogenase (HBDH), carcinoembryonic antigen (CEA), CA19-9, tissue polypeptide antigen (TPA), CA125 and sialyl TN (STN) serum levels were measured within 7 days before surgery. The tumor marker values were compared with the histopathologic diagnosis. The overall agreement between the test results and the actual outcome was calculated using Student's t test and analysis of variance (ANOVA). Survival curves were constructed according to the Kaplan-Meier method, and differences in survival were assessed with the log-rank test. The prognostic significance of tumor markers for survival was assessed in a multivariate analysis with the Cox proportional hazards model. Of the tumor markers examined in this study, CA125 showed the highest positive rate (77.6%), followed by 63.2% for STN and 55.9% for CA19-9. When the positive rate was compared according to histologic types, serous cystadenocarcinoma, mucinous cystadenocarcinoma, endometrioid adenocarcinoma and clear cell carcinoma showed the highest positive rates for CA125 (94.1%), CA19-9 (76.9%), CA125 (91.7%) and STN (75.0%), respectively. Regarding the distribution of tumor marker levels according to the FIGO stage, LDH, HBDH, TPA and CA125 were correlated with the clinical stage while CEA, CA19-9 and STN did not show any correlation. From analyses of tumor marker levels according to histologic types, all patients with a ratio of CA125 to CEA of >1, 000 had serous cystadenocarcinoma and a ratio of CA125 to CA19-9 of >50 showed serous cystadenocarcinoma or endometrioid adenocarcinoma. On the other hand, all patients with a ratio of LDH or HBDH to CA19-9 of <1.0 had mucinous cystadenocarcinoma or clear cell carcinoma. From univariate analysis, the survival time of patients with elevated CA125, TPA or STN was significantly shorter than that of patients with normal CA125, TPA or STN levels. When the Cox's proportional hazard model was used, we identified age, clinical stage, clear cell carcinoma and serum STN as independent prognostic factors. Serum CA125, TPA or STN may give significant prognostic information in epithelial ovarian carcinoma. It is noteworthy that STN has been identified as an independent prognostic factor and has a high rate of positivity in clear cell carcinoma.

Adenocarcinoma↗
PubMed1999

Dose-dependent intestinal and hepatic first-pass metabolism of midazolam, a cytochrome P450 3A substrate with differently modulated enzyme activity in rats.

The dose-dependent first-pass metabolism of midazolam, a cytochrome P450 (CYP) 3A substrate, was separately estimated in the intestine and liver after administration into a jejunal loop of rats with differently modulated enzyme activity. Modulation of CYP3A enzyme activity of Sprague-Dawley rats was performed by pretreating the rats with inducers such as dexamethasone or by co-administering ketoconazole (an inhibitor) with midazolam. Bioavailabilities of midazolam administered into the jejunal loop at a dose of 10 micromol were 12% in untreated (control) rats, and 2% in dexamethasone-pretreated rats. Co-administered ketoconazole (2 micromol) significantly increased the bioavailability to 53% and 7%, respectively, in these rats. The intestinal first-pass metabolism of midazolam administered into the jejunal loop at a dose of 50 nmol in untreated and dexamethasone-pretreated rats, estimated by the mesenteric blood-collecting method in-situ, was 25% and 49% of absorbed amount, respectively. The intestinal first-pass metabolism of midazolam was reduced when ketoconazole (0.5 micromol) was co-administered or when the dose of midazolam was increased to 0.5 micrommol in these rats. Assuming that the contribution of intestinal first-pass metabolism could be negligible when midazolam was administered at a much higher dose of 10 micromol, the estimated hepatic first-pass metabolism of midazolam at a dose of 10 micromol in untreated rats, dexamethasone-pretreated rats, untreated rats given ketoconazole, and dexamethasone-pretreated rats given ketoconazole was, respectively, 86, 97, 46, and 92% of the amounts absorbed. In conclusion, the dose-dependent intestinal first-pass metabolism and the hepatic first-pass metabolism of midazolam in rats with differently modulated CYP3A activities was quantitatively estimated by in-vivo and in-situ absorption studies.

Animals↗
PubMed1999

In-vivo and in-vitro metabolic clearance of midazolam, a cytochrome P450 3A substrate, by the liver under normal and increased enzyme activity in rats.

The metabolic clearance of midazolam, a cytochrome P450 (CYP) 3A substrate, by the liver under normal and increased enzyme activity in rats was determined in-vivo and in-vitro to elucidate the reproducibility of the in-vivo hepatic extraction ratio of midazolam from the in-vitro study. The hepatic enzyme activity was modified by pretreating rats with a CYP inducer such as dexamethasone and clotrimazole. The in-vivo hepatic extraction ratio (ERh,obs) of midazolam under a steady-state plasma concentration (approx. 3 nmolmL(-1)) in untreated (control) rats was 0.864. This value increased to 0.984 in dexamethasone-pretreated rats and to 0.964 in clotrimazole-pretreated rats. The in-vitro hepatic intrinsic clearance (CL(int,in-vitro)), expressed as mLmin(-1) (mg microsomal protein)(-1), of midazolam was estimated as Vmax (Km)(-1) by in-vitro metabolism studies using liver microsomes. The CL(int,in-vitro) value was converted to the CL(int,cal) value, expressed as mLmin(-1)kg(-1), by considering the microsomal protein content (g liver)(-1) and the microsomal protein content (g liver)(-1)kg(-1). The estimated CL(int,cal) value was then converted to the ERh value (ER(h,cal)) according to the well-stirred, the parallel-tube and the dispersion models. The ERh(h,cal) values obtained by the parallel-tube model were in good agreement with corresponding in-vivo ERh(h,obs) values. In conclusion, it was demonstrated that high hepatic clearances of midazolam under normal and increased CYP3A activity were reasonably predicted from in-vitro metabolism studies using liver microsomes.

Administration, Oral↗
PubMed1999

Effects of aluminum on plasma membrane as revealed by analysis of alkaline band formation in internodal cells of Chara corallina.

To study the mechanism of aluminum toxicity in plant cells, the effects of aluminum on alkaline band formation were analyzed in the internodal cells of Chara. After cells were treated with AlCl3, they were examined for their capacity to develop alkaline bands. Treating cells with AlCl3 medium at pH 4.5 completely inhibited alkaline band formation. When either CaCl2 or malic acid was added to the AlCl3 medium (pH 4.5), it did not produce an ameliorative effect, whereas addition of both CaCl2 and malic acid induced a significant ameliorative effect. It was found that treatment at pH 4.5 in the absence of AlCl3 strongly inhibited alkaline band formation. This inhibition by the low pH (4.5) treatment was effectively ameliorated by CaCl2. At higher pH (5.0), malic acid alone produced a significant ameliorative effect on aluminum inhibition of alkaline band formation, but CaCl2 did not. Recovery from aluminum inhibition was also studied. When cells treated with AlCl3 at pH 4.5 were incubated in artificial pond water, they could not recover the capacity to develop alkaline band. When either malic acid or CaCl2 was added to artificial pond water, cells recovered their alkaline band formation. It was concluded that one of the primary targets of aluminum is the plasma membrane and that aluminum affects the plasma membrane from the cell exterior at the beginning of the treatment (within 24 h). It was also suggested that the aluminum treatment impairs the HCO3- influx mechanism but not the OH- efflux mechanism.

Aluminum↗
PubMed1999

Thermostability reinforcement through a combination of thermostability-related mutations of N-carbamyl-D-amino acid amidohydrolase.

For the improvement of N-carbamyl-D-amino acid amidohydrolase (DCase), which can be used for the industrial production of D-amino acids, the stability of DCase from Agrobacterium sp. KNK712 was improved through various combinations of thermostability-related mutations. The thermostable temperature (defined as the temperature on heat treatment for 10 min that caused a decrease in the DCase activity of 50%) of the enzyme which had three amino acids, H57Y, P203E, and V236A, replaced was increased by about 19 degrees C. The mutant DCase, designated as 455M, was purified and its enzymatic properties were studied. The enzyme had highly increased stability against not only temperature but also pH, the optimal temperature of the enzyme being about 75 degrees C. The substrate specificity of the enzyme for various N-carbamyl-D-amino acids was changed little in comparison with that of the native enzyme. Enzymochemical parameters were also measured.

Amidohydrolases↗
PubMed1999

Enhancement of topical delivery of a lipophilic drug from charged multilamellar liposomes.

To enhance the topical delivery of rhodamine B base (Rho), a model lipophilic compound, the electrostatic interaction between the positive and negative components incorporated in the liposomal bilayer was utilized. The higher in vitro permeability to Rho in rat skin was observed with positive and neutral multilamellar liposomal preparations, the former was prepared with phosphatidylcholine (PC) and stearylamine (SA) and the latter with PC alone, than that given as a solution. Negative liposome composed of PC and dicetyl phosphate (DCP) showed lower skin permeability to Rho. To enhance the Rho retention in the skin, the electrostatic interaction between SA and DCP, which was confirmed by in vitro partition study, was utilized. By pretreating the skin surface with SA solution or empty SA liposome, the skin distribution of Rho given as DCP liposome was substantially enhanced, with increase in the PC distribution into the skin. The pretreatment effect of empty SA liposome was also observed in rats in vivo. In conclusion, it was found that negative DCP liposome provides better drug retention in the skin with lower skin permeability, and the topical drug delivery from DCP liposome was further enhanced by the pretreatment of the skin surface with empty SA liposome.

Administration, Topical↗
PubMed1999

[The effect of midazolam on the memory during cesarean section and the modulation by flumazenil].

In 30 patients (ASA-1) for elective Cesarean section who had given informed consent, characteristics of amnesia induced by midazolam (M) and their modulation by flumazenil (F) were examined. Spinal anesthesia was performed with dibucaine. After the delivery, the baby was shown to the mother. Then 21 patients were given bolus intravenous injection of M until the patient got into sleep and the inhalation of nitrous oxide mixed with oxygen was started. At the end of surgery bolus injection of F 0.1 mg was cumulatively repeated until the patient awoke. Nine patients were given only nitrous oxide and oxygen inhalation after the delivery. The remembrance of the baby face and the doses of M and F were compared. In group given M, 14 patients recalled their baby's face whereas 7 did not. The average doses of M and F in patients with memory were 69 micrograms.kg-1 and 2.5 micrograms.kg-1, respectively, whereas the average dose of M and F in patients without memory were 94 micrograms.kg-1 and 4.2 micrograms.kg-1, respectively. In the patients without M injection, all could recall the face of the baby. These results suggest that M could produce retrograde amnesia, when combined with nitrous oxide inhalation, which is not reversed by F.

Adult↗
PubMed1999

Transport of rhodamine 123, a P-glycoprotein substrate, across rat intestine and Caco-2 cell monolayers in the presence of cytochrome P-450 3A-related compounds.

Effects of cytochrome P-450 3A- and P-glycoprotein (P-gp)-related compounds, erythromycin, midazolam, ketoconazole, verapamil, and quinidine, on transport of rhodamine 123 (Rho-123), a P-gp substrate, were studied in rat intestine and in Caco-2 cells. Ileum was mainly used in rat studies because this segment showed greater P-gp-mediated Rho-123 transport. In an in vitro everted rat ileum, all the compounds examined significantly inhibited the transport of Rho-123 from serosal to mucosal surfaces across the intestine, with different inhibitory potencies among these compounds. In an in vivo rat study, the exsorption of Rho-123 from blood to the intestinal lumen, which was evaluated as exsorption clearance of Rho-123 under a steady-state plasma concentration of Rho-123, was also inhibited when these compounds were added to the intestinal lumen. Similarly, transepithelial transport of Rho-123 from the basolateral to apical side across Caco-2 cell monolayers was inhibited by these compounds. A linear relationship was observed in their inhibitory potencies on Rho-123 transport between in vitro and in vivo studies using rat ileum and between studies with rat ileum and Caco-2 cells. P-gp-mediated transport across the intestine was found to be inhibited not only by P-gp-related but also by all the cytochrome P-450 3A-related compounds examined. Within experimental error, the relative inhibitory potencies were the same between the studies with rat ileum (in vivo, in vitro) and those with Caco-2 cells. Thus, it is suggested that the function of P-gp and its sensitivity to these drugs may be similar in rat intestine and Caco-2 cells.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1999

Tissue response of a small saccular aneurysm after incomplete occlusion with a Guglielmi detachable coil.

A 49-year-old woman had a small saccular aneurysm that was incompletely occluded with a Guglielmi detachable coil (GDC). She died from rupture of another aneurysm 42 days after the treatment. Autopsy for the embolized aneurysm revealed no neoendothelium at the aneurysmal neck, but an organized thrombus was observed limited to the periphery of the aneurysmal lumen. Although isolation of the aneurysm was not apparent, loose embolization with this method may help to reinforce the aneurysmal wall.

Aneurysm, Ruptured↗
PubMed1999

[The enhancement of formalin induced agitation behavior by intrathecal administration of prostaglandin E1].

The spinal action of pro-inflammatory agent, prostaglandin E1 (PGE1) was investigated in rats, using formalin test. Sprague-Dawley rats were implanted with chronic intrathecal catheters. PGE1 0.25 microgram or 2.5 micrograms injected intrathecally. Ten minutes later, 5% formalin 50 microliters was injected to the dorsum of one hindpaw. For the time-response analysis, the total number of flinches were counted and expressed as responses per minute for each rat. For the dose response analysis, the cumulative responses per minute over the first 5 min (phase 1) and the interval 10-60 min (phase 2) following the formalin injection were calculated for each rat. PGE1 2.5 micrograms produced a significant increase of flinching in both phase 1 and phase 2. Dose dependent increase of flinching was seen only in the phase 2. Touch evoked allodynia was observed after the injection of PGE1 2.5 micrograms, which lasted about 50 minutes. The enhanced flinches induced by intrathecal PGE1 were antagonized by the coadministration of MK-801, hemoglobin or methylene blue. Allodynia was antagonized only by coadministration of methylene blue. These results indicate that hyperalgesia induced by spinal PGE1 in both phase 1 and phase 2 of the formalin test involves an increased release of glutamate and the activation of NMDA receptor in the spinal cord. The mechanism of allodynia observed in the rats given high dose of PGE1 differs from that of hyperalgesia.

Alprostadil↗
PubMed1999

Gains of 1q21-q22 and 13q12-q14 are potential indicators for resistance to cisplatin-based chemotherapy in ovarian cancer patients.

The mechanism of drug resistance in ovarian cancer is multifactorial, and accumulation of multiple genetic changes may lead to the drug-resistant phenotype. In our attempt to find characteristic genetic changes in drug-resistant tumors, we screened the whole genome for gene aberrations in 28 primary ovarian cancers using the comparative genomic hybridization method. These cancers included 14 tumors from patients who did not respond to cisplatin-based combination chemotherapy and 14 tumors from patients who had complete response to the chemotherapy. We found gains in chromosomal regions 1q21-q22 and 13q12-q14 to be related to the drug-resistant phenotype in ovarian cancer patients. Several genes encoding transcription factors, oncogenes, cell cycle regulators, and regulators of the apoptotic pathway are located on these regions of the chromosomes, and these genes are potential modulators for toxic insults in cancer cells. This is the first report that shows the relationship between certain genomic aberrations and clinical resistance to cisplatin-based chemotherapy in ovarian cancer patients based on the comparative genomic hybridization analysis. Present findings suggest that these chromosomal gains may be potential indicators for prediction of resistance in ovarian cancer patients before cisplatin-based chemotherapy.

Antineoplastic Agents↗
PubMed1999

[Remission due to CYVADIC chemotherapy of primary leiomyosarcoma derived from mesentelium of the sigmoid colon: a case report].

We report a case of leiomyosarcoma of mesenthelium origin, which was successfully treated with a combination of cyclophosphamide, vincristine, adriamycin and dacarbazine (CYVADIC). A 56-year-old woman received three courses of adjuvant CYVADIC chemotherapy after initial surgery consisting of tumorectomy, sigmoidectomy, descending colostomy, cystectomy and ureterostomy. A six-month disease-free period was attained obtained. A recurrent tumor showed remarkable reduction after three courses of CYVADIC chemotherapy. This case may be the first report of successful chemotherapy against a leiomyosarcoma of mesenthelium origin in Japan.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

[Anuria due to bilateral renal artery spasm during hysterectomy and oophorectomy].

A decrease in urinary volume during surgery is often encountered. Usually it can be treated with intravenous fluid or diuretics. We here report a rare case of intraoperative anuria in which renal blood flow ceased totally. The patient was 36 year old female (166 cm 50 kg), who was admitted for a investigations of long-term severe hypertension of unknown origin. Radiographic examination showed no adrenal tumor but a right ovarian cyst was found and suspected to be malignant, for which oophorectomy was indicated. After epidural catheterization, general anesthesia was induced by intravenous propofol and vecuronium, and maintained with epidural lidocaine and the inhalation of isoflurane and nitrous oxide mixed with oxygen. During surgery, urinary outflow decreased gradually leading to total anuria, which was resistant to intravenous fluid and furosemide. Intraoperative pyelography was performed and both kidneys and urinary tracts were not visualized. After the surgery, when the patient returned to the ward, urine began to flow. Postoperative pathological examination of the removed ovary showed a presence of renin excreting tumor cells. The anuria was considered to be the result of transient spastic obstruction of bilateral renal arteries, presumably in response to a high level of plasma renin.

Adult↗
PubMed1998

The antiarrhythmic agent cibenzoline inhibits KATP channels by binding to Kir6.2.

We reported previously that cibenzoline, an antiarrhythmic agent, inhibits the ATP-sensitive K+ (KATP) channels of pancreatic beta-cells through a binding site distinct from that for glibenclamide. In the present study, we have determined the locus of the action of cibenzoline on KATP channels reconstituted with mutant Kir6.2 and SUR1. We expressed a C-terminal truncated Kir6.2 (Kir6. 2DeltaC26) with and without SUR1 in COS7 cells. Both Kir6.2DeltaC26 and Kir6.2DeltaC26 + SUR1 formed functional KATP channels. Glibenclamide inhibited Kir6.2DeltaC26 + SUR1 channels but failed to inhibit Kir6.2DeltaC26. In contrast, cibenzoline inhibited equally Kir6.2DeltaC26 and Kir6.2DeltaC26 + SUR1 channels, in a dose-dependent manner, the half-maximal concentrations of channel inhibition being 22.2 +/- 6.1 and 30.9 +/- 9.4 microM, respectively. Furthermore, we determined also that [3H]cibenzoline bound to Kir6. 2DeltaC26. These findings confirm that cibenzoline inhibits KATP channels by a novel inhibitory mechanism in which cibenzoline directly affects the pore-forming Kir6.2 subunit rather than the SUR1 subunit.

ATP-Binding Cassette Transporters↗
PubMed1998

Cytoplasmic terminus domains of Kir6.x confer different nucleotide-dependent gating on the ATP-sensitive K+ channel.

1. In order to investigate the structural basis for the nucleotide-dependent gating of ATP-sensitive K+ channels (KATP), Kir6.1 (uKATP-1), Kir6.2 (BIR1) and chimeric channels were co-expressed with a common subtype of sulphonylurea receptor, SUR1, in COS7 cells. Representing the amino terminal domain-transmembrane domain-carboxyl-terminal domain of Kir6.1 as 1-1-1 and of Kir6.2 as 2-2-2, chimeric Kir6.x channels were constructed by swapping the amino and/or carboxyl terminal domains between Kir6.1 and Kir6.2 to give the chimeric x-1-x channels 1-1-2, 2-1-1 and 2-1-2, and the chimeric x-2-x channels 2-2-1, 1-2-2 and 1-2-1. 2. Inside-out patch clamp experiments revealed that both wild-type Kir6.1 and Kir6.2 formed inwardly rectifying K+ channels. Single-channel conductances were 36.3 and 66.1 pS, respectively. Chimeric x-1-x channels, whose transmembrane domain was that of Kir6.1, showed similar ion-pore properties to wild-type Kir6.1. Likewise, chimeric x-2-x channels had similar ion-pore properties to wild-type Kir6.2. 3. Wild-type Kir6.1 and Kir6.2 possessed distinct gating properties towards intracellular nucleotides. The activity of Kir6.1 was entirely dependent on Mg2+ and nucleotide diphosphates (NDPs) such as UDP. In contrast, Kir6.2 was activated upon excision of patch membrane. When Kir6.2 underwent rundown, UDP reactivated the channel. 4. In order to eliminate UDP dependence from Kir6.1, it was necessary to replace both N- and C-termini; chimera 2-1-2 opened in UDP-free conditions. With Kir6.2, substitution of the N-terminus with that of Kir6.1 conferred UDP dependence on chimeras 1-2-2 and 1-2-1. Chimera 2-2-1 opened in UDP-free conditions, but UDP potentiated the channel activity by > 20-fold. 5. The kinetics of UDP-dependent activation were significantly different between Kir6.1 and Kir6.2. Kir6.1 maximally activated by UDP was sensitive to intracellular ATP, although its ATP sensitivity was significantly lower than that of Kir6.2 measured in identical conditions. The kinetics of UDP-dependent activation and ATP sensitivity could be transferred between Kir6.1 and Kir6.2 only when both N- and C-termini were replaced. We therefore concluded that nucleotide-dependent gating was regulated by the N- and C-terminal domains irrespective of the transmembrane domains.

Adenosine Triphosphate↗