共查询到20条相似文献,搜索用时 15 毫秒
1.
Species specific shoot regeneration response of cotyledonary explants of Brassicas 总被引:11,自引:0,他引:11
A study of shoot regeneration from cotyledons of three basic diploid species of Brassica, B. campestris (AA), B. nigra (BB), B. oleracea (CC) and their amphidiploids B. juncea (AABB), B. napus (AACC) and B. carinata (BBCC) showed species-specific responses for in vitro shoot regeneration. Analysis of the species mean shoot regeneration response over a range of growth regulator combinations revealed that i) B. campestris is the lowest regenerating species, ii) B. nigra and B. oleracea regenerate with high frequencies, iii) In amphidiploids, the presence of B. campestris component brings down shoot regeneration frequency below the value of B. oleracea in B. napus combination and is additive of the combining genomes in B. juncea combination. In B. carinata regeneration frequencies are less than the parental diploid species, iv) Significant intraspecific genotypic differences were observed for B. nigra and B. oleracea among diploids and B. juncea and B. carinata among amphidiploids, when cotyledons of eighteen genotypes were tested in one growth regulator combination.Abbreviations MS
Murashige and Skoog (1962)
- NAA
-naphthalene acetic acid
- IAA
Indole 3-acetic acid
- BA
6-Benzyl aminopurine 相似文献
2.
Jong-Won Oh Jin-Ho Lee Kap-Soo Noh Hyune-Hwan Lee Jae-Heung Lee Hyung-Hwan Hyun 《Biotechnology letters》1991,13(10):727-732
Summary ThedapA gene (L-2,3-dihydrodipicolinate synthetase: DHDP synthetase) ofCorynebacterium
glutamicum JS231, a lysine overproducer, cloned and subcloned inE.
coli/C.
glutamicum shuttle vector pECCG117 was used to transformE.
coli threonine producer and threonine and lysine coproducer. The plasmid pDHDP5812 carryingdapA gene ofC.
glutamicum led to increase in lysine production in theseE.
coli strains. Threonine and lysine co-producerE.
coli TF1 with pDHDP5812 produced lysine with small amount of threonine. The DHDP synthetase activity ofE.
coli TF1 carrying pDHDP5812 showed high resistance toward inhibition by lysine. 相似文献
3.
Norma de Magalhães Erismann Ana M. Fernandez Jaime Baeza Juanita Freer Hector Mansilla Nelson Duran 《Biotechnology letters》1990,12(4):305-308
Summary We report the delignification ofPinus
radiata D Don,Eucalyptus
globulus andEucalyptus
grandis woods (formic acid treated and untreated) by 2 h treatment with a hemin/hydrogen peroxide system. The untreated chips and sawdust ofE.
globulus were 30% and 50% delignified respectively. No significant effects were found forP.
radiata sawdust;P.
radiata treated chips (organosolv pulp) did not show any further delignification upon hemin/peroxide action, 25% delignification was achieved in untreated chips. In the case ofE.
grandis untreated wood the delignification was better in sawdust than in chips, but in smaller percentage than in the otherEucalyptus species. This relation is maintained in substrates, treated with formic acid or untreated. The delignification of chips in both species ofEucalyptus was improved when they were pre-treated with formic acid. The loss of lignin in theE.
grandis andE.
globulus sawdust (pre-treated with formic acid) was 79% and 75% respectively. 相似文献
4.
Ketan Shah Iqbal Mehdi A. W. Khan V. C. Vora 《Applied microbiology and biotechnology》1980,10(1-2):167-169
Summary
Arthrobacter
simplex, Serratia
marcescens, Fusarium and Mycobacterium were tested for their ability to transform phytosterol to Androsta 1, 4 diene 3, 17 dione (ADD). Arthrobacter
simplex ATCC 6946 was found to be more efficient than the other species tested. 相似文献
5.
Summary Plasmids fromZ.
mobilis could be stably maintained inE.
coli HB101 in which the expression of various drug resistance markers could be monitored. A large molecular weight plasmid (5.2 kbp) ofZ.
mobilis was found to harbour the genes for mercuric chloride degradation and to confer uponE.
coli, resistance to a higher mercuric chloride concentration as compared toZ.
mobilis. The introduction of this plamsid madeE.
coli sensitive to concentrations of cadmium acetate which were originally non-inhibitory to it. 相似文献
6.
Summary A 4.1-kb cryptic plasmid, designated pCA134, has been isolated fromClostridium species. In order to develop a vector suitable for transforming saccharolytic clostridia three hybrid plasmids were constructed by inserting pCA134 into pHV32 withEcoRI, orBglII andBamHI. The newly constructed plasmids were propagated inEscherichia
coli and were used to transformBacillus
subtilis andClostridium
acetobutylicum. One of them, pCAB32 (10.1 kb), which contains chloramphenicol acetyltransferase gene and an origin of replication derived from pCA134 was introduced intoB.subtilis andC.acetobutylicum as well asE.coli. 相似文献
7.
I. S. Maddox K. Spencer J. M. Greenwood M. W. Dawson J. D. Brooks 《Biotechnology letters》1985,7(11):815-818
Summary One strain each of the fungus,Aspergillus
niger, and the yeast,Saccharomycopsis
lipolytica, were investigated for their ability to produce citric acid from the sugars present in hemicellulose hydrolysates.S.
lipolytica produced citric acid as efficiently from mannose as from glucose, but failed to assimilate xylose, arabinose or galactose.A.
niger readily assimilated mannose, xylose and arabinose, and produced citric acid from these sugars although the yields were lower than from glucose. A possible inhibitory effect of arabinose on citric acid production from other sugars was observed usingA.
niger. 相似文献
8.
Assimilation of cholesterol by some cultures of lactic acid bacteria and bifidobacteria 总被引:2,自引:0,他引:2
Summary Cultures ofStr.
thermophilus assimilated less cholesterol than those ofLactobacillus
delbrueckii subsp.bulgaricus. A significant difference was found between strains ofL.
delbrueckii subsp.bulgaricus — LB1 and LB2 and LB3 (p<0.001).Bif.
bifidum actively assimilated cholesterol, but no significant difference was observed between their two strains (p>0.05). Cultures ofL.
asidophilus assimilated significantly more cholesterol than those ofStr.
thermophilus and a commercial yoghurt culture. 相似文献
9.
Ken-ichi Ishiwata Tadashi Suzuki Satoru Iwamori Setsuo Yoshino Nobuyoshi Makiguchi 《Biotechnology letters》1990,12(3):185-190
Summary The tryptophan synthase genes,trpA andtrpB, from a moderate thermophile,Bacillus
stearothermophilus IFO13737, were expressed efficiently inEscherichia
coli. The recombinant tryptophan synthase amounted to 22% of the soluble cellular protein, and was purified to homogeneity by three steps. The enzyme is more thermostable thanE.coli tryptophan synthase, especially the subunit. The enzyme is also more resistant to sodium dodecylsulfate and methanol thanE.coli enzyme. 相似文献
10.
N. J. Moon L. C. Moon L. O. Ely J. A. Parker 《Applied microbiology and biotechnology》1981,13(4):248-250
Summary Wheat was ensiled and periodically analyzed for lactic acid bacteria present. Initially Lactobacillus
plantarum, Leuconostoc
mesenteroides, Lactobacillus
cellobiosus and Streptococcus
lactis predominated. After two to four days enterococci including S.
faecium and S.
bovis were present in high populations as well as Lactobacillus
plantarum. It was concluded that mixed populations of enterococci and L.
plantarum are active in the successful fermentation of wheat silage. 相似文献
11.
Summary Genetic determinants of the Muc+ character were investigated in two ropy strains,Lactobacillus delbrueckii ssp.bulgaricus 201 andL. casei ssp.casei NCIB 4114, which secrete a large amount of slime in culture media. Plasmid DNA analysis revealed the presence of two plasmids (4.5 and 2.3 Mdal) inL. casei ssp.casei, whileL. delbrueckii ssp.bulgaricus was plasmid free, suggesting a chromosomal location of Muc+ character in this strain. Curing experiments carried out onL. casei ssp.casei NCIB 4114 indicated a correlation between the Muc+ phenotype and the 4.5 Mdal plasmid. 相似文献
12.
Summary The instability of Lac+ and Cit+ phenotypes was investigated inLeuconostoc
mesenteroides subsp.cremoris ATCC 19245 and in four strains ofLeuconostoc
mesenteroides subsp.dextranicum. The two phenotypes were linked respectively to a 14 Mdal and a 34 Mdal plasmid in Leuconostoc mesenteroides subsp.cremoris ATCC 19245. InLeuconostoc
mesenteroides subsp.dextranicum the character Lac+ was linked to a 28 Mdal plasmid, while the Cit+ phenotype was stable. 相似文献
13.
Comparative shoot regeneration responses of three diploid Brassica species, B. campestris (AA), B. nigra (BB) and B. oleracea (CC) and their synthetic amphidiploid combinations have been investigated. The study indicates that A genome has an inhibitory effect on regeneration as evident from significantly low responses of B. juncea (AABB) and B. napus (AACC) combinations, in comparison with regeneration response of B. nigra and B. oleracea. This inhibition may arise from genomic interactions or from the B. campestris cytoplasm interacting negatively with the alien genome. Significant cytoplasmic influence on regenerability has been observed in B. carinata (BBCC) synthesised from reciprocal crosses of B. nigra and B. oleracea.Abbreviations MS
Murashige and Skoog (1962)
- IAA
Indole-3-acetic acid
- NAA
-napthaleneacetic acid
- BA
6-Benzylaminopurine 相似文献
14.
Summary Using electroporation we have transformed Cellulomonas
flavigena with a shuttle vector (pJA85) derived from the E.
coli plasmid pUC8 and the Brevibacterium
lactofermentum plasmid pULRS8. Upon transformation this plasmid was found to be stable, not to undergo detectable deletion, and to express antibiotic resistance markers originating in Brevibacterium. 相似文献
15.
Summary Intergeneric protoplast fusion betweenA.tumefaciens andB.thuringiensis was performed. The fusants exhibited some properties of both the parental strains. One of the Gram positive fusants with most of theBacillus properties showed tumor inducing capacity in pigeonpea (Cajanas
cajan). 相似文献
16.
Ligninolytic properties of different white-rot fungi 总被引:3,自引:0,他引:3
Summary Seven white-rot fungi were examined for the production of ligninase, manganese peroxidase and laccase. All these enzymes were found inTrametes gibbosa andTrametes hirsuta. Only manganese peroxidase and laccase were produced byPycnoporus cinnabarinus,Coriolopsis polyzona,Stereum hirsutum,Dichomitus squalens andGanoderma valesiacum. All fungi decolorized Poly B-411 and Indulin AT plates with low-N medium. The differences in enzyme pattern indicate that different species of fungi may employ different modes of lignin metabolism. 相似文献
17.
Summary The threonine operon fromEscherichia coli was cloned in plasmid pBR322, subcloned into the shuttle vector pCEM300 and the resulting recombinant plasmid was transferred intoBrevibacterium flavum andCorynebacterium glutamicum. The expression ofE. coli threonine genes in these coryneform bacteria was demonstrated by complementing thethrA andthrB mutations and by assaying homoserine dehydrogenase activity. 相似文献
18.
D. R. Modi A. K. Singh K. S. Rao D. Chakravarty H. N. singh 《Biotechnology letters》1991,13(11):793-798
Summary Machete resistant (Mat
r), basalin resistant (Bas
r), 3(3,4 dichlorophenyl)-1,1-dimethyl urea resistant (DCMU
r), atrazine resistant (Atr
r) and propanil resistant (Prp
r) phenotypes ofGloeocapsa sp. were cotransformed toNostoc
muscorum at high frequency. Spontaneously occurring mutants of the multiple herbicide resistant transformant containing L-methionine-DL-sulfoximine resistant (Msx
r), ethylene diamine resistant (Eda
r), or phosphinothricin resistant (Ppt
r) glutamine synthetase (GS) showed extracellular liberation of ammonia resulting from fixation of N2 under photosynthetic conditions. Results suggest a definite role of GS activity in regulation of extracellular ammonia. 相似文献
19.
Summary Starting from anileu auxotroph ofFusarium graminearum producing high levels of the mycotoxin zearalenone, selection after UV irradiation gave low-producing mutants of essentially normal morphology,zea,ileu. Heterokaryons betweenzea,ileu strains and an auxotrophic strainlz,inos derived from the lazy morphological mutant ofFusarium graminearum, which has abnormal morphology and also produces little or n zearalenone, produced significant levels (over 50% of the wild-type level) of mycotoxin. The observation confirms views as to the regulatory nature of thelazy mutation. 相似文献
20.
Stem and petiole explants, obtained from mature trees, ofAlbizzia lebbeck,Cassia fistula andC.siamea callused and differentiated shoot-buds and later shoots on B5 medium supplemented with either 0.5 mg/l IAA + 1 mg/l BAP or BM + 2 mg/l NAA + 0.5 mg/l BAP. The stem explants were more responsive than the petiole explants. InA.lebbeck, the IAA substituted medium favoured differentiation from both types of explants. However, inC.fistula, the type of explants rather than the medium composition had an overriding influence on shoot differentiation since those from petiole hardly responded in either medium. It has been possible to obtain plantlets from bothA.lebbeck andC.fistula under conditions conducive to rooting. Plantlets ofA.lebbeck have also been successfully transferred to the field. 相似文献