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1.
Hydrogen peroxide was formed in isolated cell walls from Marchantiapolymorpha L. in the presence of MnCl2 by either NADH or NADPHoxidation. This reaction was stimulated by phenols such as 2,4-dichlorophenolor p-coumarate, suggesting a reaction similar to that proposedfor the last step of lignification in higher plant cells, althoughbryophytes have been reported to be devoid of lignin. (Received June 16, 1987; Accepted March 3, 1987) 相似文献
2.
Complete nucleotide sequence of the mitochondrial DNA from a liverwort,Marchantia polymorpha 总被引:1,自引:1,他引:0
Kenji Oda Katsuyuki Yamato Eiji Ohta Yasukazu Nakamura Miho Takemura Naoko Nozato Kinya Akashi Takeshi Kanegae Yutaka Ogura Takayuki Kohchi Kanji Ohyama 《Plant Molecular Biology Reporter》1992,10(2):105-163
Libraries of cosmid and plasmid clones covering the entire region of mtDNA from the liverwortMarchantia polymorpha were constructed. These clones were used for the determination of the complete nucleotide sequence of the liverwort mtDNA
totally 186,608 bp (GenBank no. M68929) and including genes for 3 species of ribosomal RNAs, 29 genes for 27 species of transfer
RNAs, and 30 genes for functionally known proteins (16 ribosomal proteins, 3 subunits of cytochromec oxidase, apocytochromeb protein, 3 subunits of H+-ATPase, and 7 subunits of NADH ubiquinone oxidoreductase). The genome also contains 32 unidentified open reading frames.
Thus the complete nucleotide sequences from both chloroplast and mitochondrial genomes have been determined in the same organism.
Plasmid clones are available upon the request.
Gene names are represented according to Lonsdale and Leaver (1988) with modifications recommended by Lonsdale (personal communication). 相似文献
3.
Chromosomal localization of the Epstein-Barr virus (EBV) genome in Bloom's syndrome B-lymphoblastoid cell lines transformed with EBV 总被引:3,自引:0,他引:3
The localization of the Epstein-Barr virus (EBV) genome in chromosomes of human B-lymphoblastoid cell lines (LCLs) transformed with EBV, and the effect of EBV DNA on the level of sister chromatid exchange (SCE) in Bloom's syndrome (BS) B-LCLs, were examined with chromosomal in situ hybridization techniques using a 3H-EBV DNA probe. EBV DNA was detected in chromosomes 1–5 and 13–15 at specific G band regions in BS as well as in normal B-LCLs, regardless of SCE. Several chromosomal sites (1p31, 1q31, 4q22–24, 5q21, 13q21, 14q21) carrying EBV DNA seemed to be very characteristic in normal as well as in BS B-LCLs. There was no statistically significant difference in silver grain counts due to EBV DNA and their distribution in different chromosomes or groups among normal and BS B-LCLs with normal and high SCE. These findings strongly indicate that EBV infection did not introduce a correcting factor for BS SCE. 相似文献
4.
Nucleotide sequence and gene organization of ColE1 DNA 总被引:48,自引:0,他引:48
The primary structure of the plasmid ColE1 DNA has been determined. The plasmid DNA consists of 6646 base pairs (molecular mass of 4.43 MDa) and is 48.46% in GC content. The phi 80 trp insert of the composite plasmid of ColE1, pVH51, has also been determined. The determination of the nucleotide sequence of ColE1 DNA provides the basis for examining the relationships between the DNA sequence and the gene organization of the plasmid. The focus of this paper is to use this sequence data coupled with a review of the literature and our own work to examine the nine known functional regions of ColE1: imm (colicin E1 immunity), rep (replication function), inc (plasmid incompatibility and copy number control), bom (basis of mobility), rom (modulator of inhibition of primer formation by RNA I), mob (plasmid mobilization), cer (determinant for conversion of plasmid multimers to monomers), exc (plasmid entry exclusion), cea (structural gene for colicin E1), and kil (structural gene for the Kil protein). 相似文献
5.
Kanji Ishizaki Asao Noda Mituo Ikenaga Kenji Ida Keiichi Omoto Yusuke Nakamura Ken-ichi Matsubara 《Human genetics》1985,71(3):261-262
Summary The plasmid clone which contains human salivary amylase cDNA was used to detect restriction fragment length polymorphisms
(RFLPs). After double digestion with Pst 1 and Bam H1, a polymorphism with two alleles was observed. In Japanese, frequencies of these alleles, tentatively called 5.7kb and 6.5kb
fragment alleles, are 0.55 and 0.45, respectively. 相似文献
6.
A small plasmid-specified RNA (RNA I) inhibits formation of the RNA primer for CoIE1 DNA replication by binding to its precursor (RNA II). Binding is modulated by the plasmid-specified Rom protein. Both in the presence and absence of Rom, binding starts with interaction between loops of RNAs. To understand the mechanism of binding, we examined the interactions of pairs of single stem-loops that are complementary fragments of RNA I and RNA II. We found that these complementary single stem-loops bind to each other at their loops, forming an RNAase V1-sensitive structure. Rom protects the complex from cleavage and from alkylation of phosphate groups by ethyinitrosourea. A single dimer of Rom binds to the complex by recognizing the structure rather than its exact nucleotide sequence. Rom enhances complex formation by decreasing the rate of dissociation of the complex. Structures of RNA complexes formed in the presence and absence of Rom are proposed. 相似文献
7.
Shinichi Kitamura Takashi Hirano Kenichi Takeo Mitsuru Mimura Kanji Kajiwara Bjrn T. Stokke Tsutomu Harada 《International journal of biological macromolecules》1994,16(6)
The conformation and dilute solution properties of (2→1)-β-d-fructan in aqueous solution were studied by gel permeation chromatography, low-angle laser light-scattering photometry, viscometry, small-angle X-ray scattering and electron microscopy. Fractions covering a broad range of weight-average molecular weights (Mw) from 1.49 × 104 to 5.29 × 106 were obtained from a native sample by ultrasonic degradation and fractional precipitation. For Mw < 4 × 104, the intrinsic viscosity [η] varies with Mw0.71, indicating that the fructan chain behaves as a random coil expanded by an excluded-volume effect in this molecular weight region. For Mw > 105, [η] exhibits an unusually weak dependence on Mw and finally becomes almost independent of molecular weight. This behaviour is interpreted in terms of a globular conformation of the high-molecular-weight fructan molecules. Small-angle X-ray-scattering measurements and electron microscopic observations support this interpretation of the values of [η] observed. 相似文献
8.
9.
Yoshihiro Izumi Kanji Ono Masayuki Takamiya Kiichi Fukui 《Journal of plant research》1993,106(4):319-325
Using cultured cells of the hornwortAnthoceros punctatus, the change in the relative chloroplast DNA content in each stage of chloroplast division was investigated to clarify the
relationship between the division cycle of a chloroplast and a cell nucleus. Samples of cultured cells were stained with 4′,6-diamidino-2-phenylindole
(DAPI) and then observed with an epifluorescence microscope and a chromosome image analyzing system (CHIAS). A chloropiast
in cultured cells duplicated DNA with an increase in size. When a chloroplast began to divide, it was constricted in the middle,
taking a dumbbell shape, and then divided into two daughter chloroplasts. In cultured cells of this species, the pattern of
quantitative change of chloroplast DNA, that is, the DNA replication pattern of chloroplasts, corresponded to that of cell
nuclear DNA in mitosis. 相似文献
10.
Kohei Irifune Kanji Ono Misa Takahashi Hideko Murakami Hiromichi Morikawa 《Transgenic research》1996,5(5):337-341
Suspension-cultured cells (A-18 line) of the liverwortMarchanta polymorpha were bombarded by a pneumatic particle gun with plasmid pCH harbouring the hygromycin phosphotransferase (HPT) gene (hpt) under the control of the cauliflower mosaic virus (CaMV) 35 S promoter and the nopaline synthase polyadenylation region. Nine weeks after bombardments, 128 hygromycin-resistant calluses were obtained from an approximate total of 7×106 cells. Ten cell lines chosen randomly were analysed further. Southern blot analysis showed that all of the ten lines contain thehpt gene in the genome, demonstrating that these lines are transformants. An HPT enzyme activity assay confirmed the expression of the gene in all of the transformant lines. 相似文献