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T Nohara

Publications and source records attributed to T Nohara.

At least 19 recordsLinked to original sources
PubMed1995

Isolation and characterization of the cDNA for pea chloroplast SecA. Evolutionary conservation of the bacterial-type SecA-dependent protein transport within chloroplasts.

We report here the isolation of the cDNA for pea chloroplast SecA. Pea SecA encodes a polypeptide of 1,011 amino acids and shows high sequence similarity with cyanobacterial SecA. Pea SecA was synthesized as a larger precursor and was imported into isolated chloroplasts in vitro. The purified pea SecA, which was expressed in Escherichia coli cells, stimulated the in vitro import of the 33 kDa protein of the oxygen-evolving complex into thylakoids. These results indicate that higher plant chloroplasts contain a bacterial-type SecA protein-dependent system for the intraorganellar protein transport into thylakoids.

Adenosine Triphosphatases↗
PubMed1995

Spectral analyses of R-R interval and systolic blood pressure in diabetic autonomic neuropathy.

We studied autonomic nervous system function using the principle of maximum entropy (ME) to perform spectral analyses of the R-R interval and systolic blood pressure in 32 diabetic patients and 40 healthy controls. The R-R interval and systolic blood pressure were measured using a continuous, noninvasive monitoring system. The power spectra of both the R-R interval (RR) and systolic blood pressure (SYS) were obtained using ME and the areas of two frequency components were measured: a low- (LFC) and a high-frequency component (HFC). The RR-LFC, RR-HFC and SYS-LFC of diabetic patients were significantly smaller than those of healthy controls. The results of the spectral analyses in diabetic patients correlated with neither disease duration nor nephropathy, while the SYS-LFC showed significant correlations with both retinopathy and the delay in median motor nerve conduction velocity. In the mild autonomic neuropathy group, the RR-LFC and SYS-LFC were not differ from those of healthy controls or patients without autonomic neuropathy. However, the RR-HFC was significantly smaller than that of healthy controls or patients without atonomic neuropathy. In the setting of mild diabetic autonomic neuropathy, it was suggested that cardiac parasympathetic dysfunction preceded both alpha and beta sympathetic dysfunction.

Adult↗
PubMed1995

Cycloartane-type glycosides from thalictri herba.

Two new cycloartane-type glycosides, designated as thalictosides V and IX, were isolated from the methanolic extract of Thalictri Herba (Takatogusa), the dried aerial parts of Thalictrum sp. plants. Their chemical structures have been characterized as 3-O-monodesmoside and the 3,21-di-O-bisdesmoside of 3 beta,22 zeta,30-trihydroxycycloart-24-en-21-oic acid, by chemical and spectroscopic evidence.

Carbohydrate Sequence↗
PubMed1995

Flavonol sinapoyl glycosides from leaves of Thevetia peruviana.

From the leaves of Thevetia peruviana four new flavonol glycosides, kaempferol 3-glucosyl(1 --> 4) [6"'-sinapoylglucosyl] (1 --> 2) galactoside and 3-[2""-sinapoylglucosyl](1 --> 4)[6"'-sinapoylglucosyl](1 --> 2)galactoside and kaempferol and quercetin 3-[6"'-sinapoylglucosyl](1 --> 2)galactoside were isolated, together with the known compounds, kaempferol and quercetin 3-glucosyl(1 --> 2)galactoside. The glycosides were characterized from FAB mass, 1H and 13C NMR and UV spectral data.

Carbohydrate Conformation↗
PubMed1995

Steroidal alkaloids of Fritillaria maximowiczii.

From the bulbs of Fritillaria maximowiczii, in addition to the known jerveratrin alkaloid, kuroyurinidine, three new steroidal alkaloids, 23-isokuroyurinidine, 15,16-seco-22 alpha H, 25 beta H-solanida-5,14-dien-3 beta-ol O-beta-D-glucopyranosyl-(1-->4)-beta-D-xylopyranoside and hapepunine 3-O-beta-cellobioside have been isolated and structurally elucidated.

Alkaloids↗
PubMed1995

Oleanene-type triterpene glycosides from Puerariae Radix. II. Isolation of saponins and the application of tandem mass spectrometry to their structure determination.

A continuing study of the ingredients of Puerariae Radix, the roots of Pueraria lobata (WILLD.) OHWI, which is one of the most important crude drugs, has resulted in the first isolation of four new oleanene-type triterpene glycosides, named kudzusaponins SA1, SA2, SA3 and C1 (1-4). Their structures were determined to be 3-O-beta-D-galactopyranosyl-(1-->2)-beta-D-glucuronopyranosyl soyasapogenol A (1), 3-O-beta-galactopyranosyl-(1-->2)-beta-D-glucuronopyranosyl soyasapogenol A 22-O-alpha-L-arabinopyranoside (2), 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-galactopyranosyl-(1-->2)-D- glucuronopyranosyl kudzusapogenol C 21-O-beta-D-glucopyranoside (4), respectively. The usefulness of tandem mass spectrometry in the structural determination of oleanene-type triterpene bisdesmosides is also discussed.

Carbohydrate Conformation↗
PubMed1995

Spirostanol glycosides from Peliosanthes sinica.

Three new spirostanol glycosides, peliosanthosides A--C, were isolated from the whole plants of Peliosanthes sinica, along with two known ones. Their structures were elucidated by means of chemical and spectral evidence.

Carbohydrate Sequence↗
PubMed1995

Five new triterpene glycosides from Wisteria brachybotrys (Leguminosae).

From the vines of Wisteria brachybotrys (Leguminosae), five new oleanene glycosides, called wistariasaponins YC1,2, B3 and A2,3, together with four known ones were isolated. Their structures have been elucidated to be 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl-(1-->2)-beta-D- glucuronopyranosyl yunganogenin C 21-O-beta-D-glucopyranoside (1), 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-galactopyranosyl-(1-->2)-beta -D- glucuronopyranosyl yunganogenin C 21-O-beta-D-glucopyranoside (2), 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl-(1-->2)-beta- -D-glucuronopyranosyl wistariasapogenol B 30-O-beta-D-glucopyranoside (3), 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl-(1-->2)-beta-D- glucuronopyranosyl wistartiasapogenol A 30-O-beta-D-glucopyranoside (4) and 3-O-beta-D-galactopyranosyl-(1-->2)-beta-D-glucuronopyranosyl wistariasapogenol A 30-O-beta-D-glucopyranoside (5), respectively.

Carbohydrate Sequence↗
PubMed1994

Identification of the SecA protein homolog in pea chloroplasts and its possible involvement in thylakoidal protein transport.

Recently, we identified the SecA and SecY proteins in the cyanobacterium Synechococcus PCC7942. Antibodies raised against cyanobacterial SecA specifically reacted with a 110-kDa protein of pea chloroplasts, suggesting the presence of SecA in higher plant chloroplasts. A part of the pea secA cDNA was polymerase chain reaction-amplified with degenerated oligonucleotide primers and with pea cDNA as a template. The deduced amino acid sequence shows 62% identity with cyanobacterial SecA and 52% identity with Escherichia coli SecA. Antibodies raised against the pea SecA fragment, which was expressed in E. coli cells from the obtained polymerase chain reaction-amplified cDNA, reacted with the 110-kDa chloroplast protein; the 110-kDa protein was mainly found in the stroma but partly in the thylakoid membrane. The anti-pea SecA IgG inhibited the in vitro import of the 33-kDa protein of the oxygen-evolving complex, but not of the 23-kDa protein of the oxygen-evolving complex, into thylakoids. These results suggest that SecA facilitates transport of a subset of thylakoid lumenal proteins including the 33-kDa protein into thylakoids. We propose that a bacterial-type Sec protein-dependent transport system operates for protein transport into thylakoids in higher plant chloroplasts.

Amino Acid Sequence↗
PubMed1994

Identification and characterization of the sec-A protein homologue in the cyanobacterium Synechococcus PCC7942.

The secA gene product mediates protein translocation across the cytoplasmic membrane in Escherichia coli. We have cloned a gene homologous to secA from the genome of the cyanobacterium Synechococcus PCC7942. The deduced amino acid sequence, 948 amino acids long, shows 43% homology with that of the E. coli secA and 47-48% homology with those of the algal plastid secA genes. Upon subcellular fractionation, the cyanobacterial SecA protein was mainly found as soluble homodimer in the cytosol, but the remaining small but distinct fraction was associated with both the cytoplasmic and thylakoid membranes. The SecA protein likely participates in protein translocation across both the cytoplasmic and thylakoid membranes in cyanobacterial cells.

Adenosine Triphosphatases↗
PubMed1994

Ergostane glycosides from Petunia hybrida.

Six new ergostane glycosides, designated as petunioside A, petunioside B, 24-epipetunioside B, petunioside C, 24-epipetunioside C and petunioside D, were isolated from the methanolic extract of the fresh aerial parts of Petunia hybrida. Their structures were determined by means of spectroscopic analysis and single crystal X-ray analysis.

Carbohydrate Conformation↗
PubMed1994

Steroidal glycosides from Capsicum annuum.

Four new steroidal glycosides, named capsicosides A-D together with proto-degalactotigonin, were isolated from the roots and seeds of Capsicum annuum var. conoides and Capsicum annuum var. fasciculatum. On the basis of detailed chemical and spectroscopic evidence, the structures of capsicosides A-D were shown to be furostanol glycosides corresponding to gitogenin and tigogenin oligoglycosides. Capsicoside A was regarded as the same compound as the previously described capsicoside, whose structure now needs to be revised according to the data presented in this report.

Capsicum↗
PubMed1994

Triterpene glycosides from thalictri herba. II.

Five new triterpene glycosides were isolated from the methanolic extract of Thalictri Herba (Takatogusa), the dried aerial parts of Thalictrum sp. plants (Ranunculaceae). They were designated as thalictosides III (1) and IV (2), being cycloartane-type glycosides, and thalictosides VI (3), VII (4) and VIII (5), being oleanene-type glycosides. By chemical and spectroscopic evidence, their structures were elucidated as 22R-21S,23R-epoxy- and 22R-21R,23R-epoxy-21-methoxycycloart-24-en-3 beta,22,30-triol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->6)]- beta-D-glucopyranosides (1 and 2, respectively), 3-O-beta-D-glucopyranosyl-(1-->3)-alpha-L- rhamnopyranosyl-(1-->4)-beta-D-xylopyranosyl hederagenin 28-O-beta-D-glucopyranosyl ester (3) and 3-O-alpha-L-rhamnopyranosyl-(1-->3)-beta-D-glucopyranosyl-(1-->3)-alpha- L- rhamnopyranosyl-(1-->4)-beta-D-xylopyranosyl oleanolic acid and hederagenin 28-O-beta-D-glucopyranosyl esters (4 and 5, respectively).

Carbohydrate Sequence↗
PubMed1994

Two new triterpenoidal glycosides from Medicago polymorpha L.

Two new triterpenoid glycosides called medicago-saponins P1 (1) and P2 (2) were isolated together with five known glycosides from the aerial parts of Medicago polymorpha L. (Leguminosae). The structures of 1 and 2 were determined to be 3-O-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl caulophyllogenin 28-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranoside and the desglucoside of 1.

Carbohydrate Sequence↗
PubMed1994

Five new triterpene glycosides from Russell lupine.

In a continuing study on the ingredients of Lupinus genus, we examined the oligoglycoside constituents of the Russell lupine (L. polyphyllus x L. arboreus hybrid). Five new oleanene glycosides, called Lupinosides PA1-5 (1-5), together with three known ones were isolated. Their structures of 1-5 were determined to be 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-galactopyranosyl- (1-->2)-beta-D-glucuronopyranosyl soyasapogenol A 21-O-beta-D- xylopyranoside (1), 3-O-beta-D-galactopyranosyl-(1-->2)-beta-D-glucuronopyranosyl soyasapogenol A 21-O-beta-D-xylopyranoside (2), 3- O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-galactopyranosyl-(1-->2)-beta-D -glucuronopyranosyl kudzusapogenol A 21-O-beta-D- xylopyranoside (3), 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D- galactopyranosyl-(1-->2)-beta-D-glucuronopyranosyl soyasapogenol B 22-O-alpha-L-rhamnopyranoside (4), and 3-O-alpha-L-rhamnopyranosyl-(1-->2)- beta-D-galactopyranosyl-(1-->2)-beta-D-glucuronopyranosyl soyasapogenol B 22-O- beta-D-glucopyranosyl-(1-->4)-alpha-L-rhamnopyranoside (5), respectively.

Carbohydrate Sequence↗
PubMed1992

Three new oleanene glycosides from Sophora flavescens.

Three new oleanene glycosides, sophoraflavosides II-IV (2-4) were isolated together with sophoraflavoside I (1) as the corresponding methyl ester forms from Sophorae Radix, the fresh roots of Sophora flavescens AITON (Leguminosae). Their structures have been elucidated as oxytrogenin 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-galactopyranosyl-(1-->2)-beta -D- glucuronopyranoside (2), 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-galactopyranosyl-(1-->2)-beta -D-glucuronopyranosyl oxytrogenin 22-O-alpha-L-arabinopyranoside (3) and 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-galactopyranosyl-(1-->2)-beta -D-glucuronopyranosyl oxytrogenin 22-O-beta-D-glucopyranosyl-(1-->2)-alpha-L-arabinopyranoside (4), along with unambiguous characterization as 3 beta,22 beta,24-trihydroxyolean-12-en-29-oic acid for their sapogenol, named oxytrogenin (5) on the bases of chemical reactions and spectral analyses.

Carbohydrate Sequence↗
PubMed1992

Triterpene glycosides from the bark of Robinia pseudo-acacia L. I.

From the bark of Robinia pseudo-acacia L., five new triterpene glycosides, robiniosides A-D (3, 5-7) and compound III (4), were isolated and their structures were elucidated as 3-O-alpha-L-rhamnopyranosyl(1-->2)-beta-D-glucopyranosyl(1-->2)-beta-D- glucuronopyranosyl 3 beta,22 beta-dihydroxyolean-12-en-29-oic acid (3), 3-O-alpha-L-rhamnopyranosyl(1-->2)-beta-D-galactopyranosyl(1-->2)-beta-D -glucuronopyranosyl 3 beta,22 beta,24-trihydroxyolean-12-en-29-oic acid (4), whose sapogenol was unambiguously characterized and designated as oxytrogenin, 3-O-alpha-L-rhamnopyranosyl(1-->2)-beta-D-glucopyranosyl(1-->2)-beta-D glucuronopyranosyl oxytrogen (5), 3-O-alpha-L-rhamnopyranosyl(1-->2)-beta-D galactopyranosyl(1-->2)-beta-D-glucuronopyranosyl oxytrogenin 22-O-alpha-L-rhamnopyranoside (6), 3-O-alpha-L- rhamnopyranosyl(1-->2)-beta-D-glucopyranosyl(1-->2)-beta-D-glucuronop yranosyl oxytrogenin 22-O-alpha-L-rhamnopyranoside (7), respectively, together with two known triterpene glycosides, kaikasaponin III (1) and 3-O-alpha-L-rhamnopyranosyl(1-->2)-beta-D-galactopyranosyl(1-->2)-beta-D - glucuronopyranosyl 3 beta,22 beta-dihydroxyolean-12-en-29-oic acid (2).

Carbohydrate Sequence↗