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1.
Two strains PB196T and PB62T of Gram-negative, non-motile, and non-spore-forming bacteria, were isolated from soil in South Korea and characterized to
determine their taxonomic positions. 16S rRNA gene sequence analysis showed that the two strains belonged to the genus Sphingomonas. The highest degree of sequence similarity of strain PB196T was found with PB62T (98.9%), Sphingomonas humi PB323T (98.9%), Sphingomonas kaistensis PB56T (98.2%), and Sphingomonas astaxanthinifaciens TDMA-17T (98.0%). The highest degree of sequence similarity of strain PB62T was found with Sphingomonas humi PB323T (98.8%), Sphingomonas astaxanthinifaciens TDMA-17T (98.2%), and Sphingomonas kaistensis PB56T (98.1%). Chemotaxonomic data revealed that they possessed ubiquinone-10 (Q-10) as common in the genus Sphingomonas, that the predominant fatty acids were summed feature 7 (C18:1
ω7c/ω9t/ω12t), summed feature 4 (C16:1
ω7c/C15:0 iso 2OH), C16:0, and C17:1
ω6c, and that they contained sphingoglycolipid, phosphatidylglycerol (PG), and phosphatidyle-thanolamine (PE) in common but they
showed difference for diphosphatidylglycerol (DPG). Based on these data, PB196T (=KCTC 12339T =JCM 16604T) and PB62T (=KCTC 12336T =JCM 16605T =KEMB 9004-005T) should be classified as type strains of two novel species, for which the names Sphingomonas rosea sp. nov. and Sphingomonas swuensis sp. nov. are proposed, respectively. 相似文献
2.
This study focused on the physiological, chemotaxonomic, and genotypic characteristics of two thermophilic spore-forming sulfate-reducing bacterial strains, 435T and 781, of which the former has previously been assigned to the subspecies “Desulfotomaculum nigrificans subsp. salinus”. Both strains reduced sulfate with the resulting production of H2S on media supplemented with H2 + CO2, formate, lactate, pyruvate, malate, fumarate, succinate, methanol, ethanol, propanol, butanol, butyrate, valerate, or palmitate. Lactate oxidation resulted in acetate accumulation; butyrate was oxidized completely, with acetate as an intermediate product. Growth on acetate was slow and weak. Sulfate, sulfite, thiosulfate, and elemental sulfur, but not nitrate, served as electron acceptors for growth with lactate. The bacteria performed dismutation of thiosulfate to sulfate and hydrogen sulfide. In the absence of sulfate, pyruvate but not lactate was fermented. Cytochromes of b and c types were present. The temperature and pH optima for both strains were 60–6°C and pH 7.0. Bacteria grew at 0 to 4.5–6.0% NaCl in the medium, with the optimum being at 0.5–1.0%. Phylogenetic analysis based on a comparison of incomplete 16S rRNA sequences revealed that both strains belonged to the C cluster of the genus Desulfotomaculum, exhibiting 95.5–98.3% homology with the previously described species. The level of DNA–DNA hybridization of strains 435T and 781 with each other was 97%, while that with closely related species D. kuznetsovii 17T was 51–52%. Based on the phenotypic and genotypic properties of strains 435T and 781, it is suggested that they be assigned to a new species: Desulfotomaculum salinum sp. nov., comb. nov. (type strain 435T = VKM B 1492T). 相似文献
3.
Coulibaly I Revol B Noirot M Poncet V Lorieux M Carasco-Lacombe C Minier J Dufour M Hamon P 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2003,107(6):1148-1155
An interspecific cross (BC 1) involving a species with one of the largest genomes in the Coffea genus [Coffea heterocalyx (HET), qDNA = 1.74 pg] and a species with a medium-sized genome [Coffea canephora (CAN), qDNA = 1.43 pg] was studied using two types of molecular markers, AFLP and SSR. One hundred and eighty eight AFLP bands and 34 SSR primer pairs were suitable for mapping. The total map length was 1,360 cM with 190 loci distributed in 15 linkage groups. The results were compared to those obtained previously on an interspecific BC 1 progeny involving a species with a medium-sized genome (Coffea liberica var dewevrei, DEW) and a species with one of the smallest genomes (Coffea pseudozanguebariae, PSE). They are discussed relative to three main points: (1) the relevance of the different marker types, (2) the genomic distribution of AFLP and SSR markers, and (3) the relation between AFLP polymorphism and genome size.Communicated by H.F. Linskens 相似文献
4.
The lipase Lip2 of the edible basidiomycete, Pleurotus sapidus, is an extracellular enzyme capable of hydrolysing xanthophyll esters with high efficiency. The gene encoding Lip2 was expressed
in Escherichia coli TOP10 using the gene III signal sequence to accumulate proteins in the periplasmatic space. The heterologous expression under
control of the araBAD promoter led to the high level production of recombinant protein, mainly as inclusion bodies, but partially
in a soluble and active form. A fusion with a C-terminal His tag was used for purification and immunochemical detection of
the target protein. This is the first example of a heterologous expression and periplasmatic accumulation of a catalytically
active lipase from a basidiomycete fungus. 相似文献
5.
Matías Maggi Natalia Damiani Sergio Ruffinengo David De Jong Judith Principal Martín Eguaras 《Experimental & applied acarology》2010,50(3):269-279
We undertook a field study to determine whether comb cell size affects the reproductive behavior of Varroa destructor under natural conditions. We examined the effect of brood cell width on the reproductive behavior of V. destructor in honey bee colonies, under natural conditions. Drone and worker brood combs were sampled from 11 colonies of Apis mellifera. A Pearson correlation test and a Tukey test were used to determine whether mite reproduction rate varied with brood cell
width. Generalized additive model analysis showed that infestation rate increased positively and linearly with the width of
worker and drone cells. The reproduction rate for viable mother mites was 0.96 viable female descendants per original invading
female. No significant correlation was observed between brood cell width and number of offspring of V. destructor. Infertile mother mites were more frequent in narrower brood cells. 相似文献
6.
Background
The presence of β-lactamases in Y. enterocolitica has been reported to vary with serovars, biovars and geographical origin of the isolates. An understanding of the β-lactamases in other related species is important for an overall perception of antibiotic resistance in yersiniae. The objective of this work was to study the characteristics of β-lactamases and their genes in strains of Y. intermedia and Y. frederiksenii, isolated from clinical and non-clinical sources in India. 相似文献7.
Root segments from seedlings of Panax ginseng produced adventitious roots directly when cultured on 1/2 MS solid medium lacking NH4NO3 and containing 3.0 mg l−1 IBA. Using this adventitious root formation, we developed rapid and efficient transgenic root formation directly from adventitious
root segments in P. ginseng. Root segments were co-cultivated with Agrobacterium tumefaciens (GV3101) caring β-glucuronidase (GUS) gene. Putative transgenic adventitious roots were formed directly from root segments on medium with 400 mg l−1 cefotaxime and 50 mg l−1 kanamycin. Kanamycin resistant adventitious roots were selected and proliferated as individual lines by subculturing on medium
with 300 mg l−1 cefotaxime and 50 mg l−1 kanamycin at two weeks subculture interval. Frequency of transient and stable expression of GUS gene was enhanced by acetosyringon (50 mg l−1) treatment. Integration of transgene into the plants was confirmed by the X-gluc reaction, PCR and Southern analysis. Production
of transgenic plants was achieved via somatic embryogenesis from the embryogenic callus derived from independent lines of
adventitious roots. The protocol for rapid induction of transgenic adventitious roots directly from adventitious roots can
be applied for a new Agrobacterium tumefaciens-mediated genetic transformation protocol in P. ginseng. 相似文献
8.
Recently, the gene coding for a new beta-glucuronidase enzyme has been identified and cloned from Streptococcus equi subsp. zooepidemicus. This is another report of a beta-glucuronidase gene cloned from bacterial species. The ORF Finder analysis of a sequenced
DNA (EMBL, AJ890474) revealed a presence of 1,785 bp large ORF potentially coding for a 594 aa protein. Three protein families
in (Pfam) domains were identified using the Conserved Domain Database (CDD) analysis: Pfam 02836, glycosyl hydrolases family
2, triose phosphate isomerase (TIM) barrel domain; Pfam 02837, glycosyl hydrolases family 2, sugar binding domain; and Pfam
00703, glycosyl hydrolases family 2, immunoglobulin-like beta-sandwich domain. To gain more insight into the enzymatic activity,
the domains were used to generate a bootstrapped unrooted distance tree using ClustalX. The calculated distances for two domains,
TIM barrel domain, and sugar-binding domain were comparable and exhibited similarity pattern based on function and thus being
in accordance with recently published works confirming beta-glucuronidase activity of the enzyme. The calculated distances
and the tree arrangement in the case of centrally positioned immonoglobulin-like beta-sandwich domain were somewhat higher
when compared to other two domains but clustering with other beta-glucuronidases was rather clear. Nine proteins, including
beta-glucuronidases, beta-galactosidase, and mannosidase were selected for multiple alignment and subsequent distance tree
creation. 相似文献
9.
Bimal Kumar Ghimire Eun Soo Seong Jung Dae Lim Kweon Heo Myong Jo Kim Ill-Min Chung John A. Juvik Chang Yeon Yu 《Plant Cell, Tissue and Organ Culture》2008,95(3):265-274
Efficient transformation of leaf disc-derived callus of Codonopsis lanceolata was obtained using Agrobacterium tumefaciens strain LBA4404 harboring a binary vector, pYBI121, that carries the neomycin phosphotransferase (npt II) gene as a selectable marker. The green shoots recovered from agroinfected explants on selection medium (containing 0.1 mg/l
α-naphthaleneacetic acid (NAA), 1 mg/l 6-benzylaminopurine (BAP), 100 mg/l kanamycin, and 250 mg/l cefotaxime) were rooted
on Murashige and Skoog (MS) medium supplemented with 2 mg/l IBA and 10 mg/l kanamycin. To optimize the transformation conditions,
several factors were assessed, including the co-cultivation period, the duration of pre- and post-culture in darkness and
light, the kanamycin concentration, and the Agrobacterium densities. We produced transgenic Codonopsis lanceolata overexpressing γ-tocopherol methyltransferase (γ-TMT) by this protocol. Moreover, the α-tocopherol content of the plants was enhanced by the overexpression of this gene.
Bimal Kumar Ghimire and Eun Soo Seong contributed equally to this work. 相似文献
10.
Dana Bernátová 《Biologia》2008,63(2):175-176
The paper brings information on an isolated occurrence and morphological characters of Carex × involuta and C. juncella populations in the Vel’ká Fatra Mts. Their presence has been known neither from the territory of Slovakia nor from the whole
Western Carpathians till now. 相似文献
11.
In Escherichia coli cellular levels of pppGpp and ppGpp, collectively called (p)ppGpp, are maintained by the products of two genes, relA and spoT. Like E. coli, Vibrio cholerae also possesses relA and spoT genes. Here we show that similar to E. coli, V. cholerae ΔrelA cells can accumulate (p)ppGpp upon carbon starvation but not under amino acid starved condition. Although like in E. coli, the spoT gene function was found to be essential in V. cholerae
relA
+ background, but unlike E. coli, several V. cholerae ΔrelA ΔspoT mutants constructed in this study accumulated (p)ppGpp under glucose starvation. The results suggest a cryptic source of
(p)ppGpp synthesis in V. cholerae, which is induced upon glucose starvation. Again, unlike E. coli ΔrelA ΔspoT mutant (ppGpp0 strain), the V. cholerae ΔrelA ΔspoT mutants showed certain unusual phenotypes, which are (a) resistance towards 3-amino-1,2,4-triazole (AT); (b) growth in nutrient
poor M9 minimal medium; (c) ability to stringently regulate cellular rRNA accumulation under glucose starvation and (d) initial
growth defect in nutrient rich medium. Since these phenotypes of ΔrelA ΔspoT mutants could be reverted back to ΔrelA phenotypes by providing SpoT in trans, it appears that the spoT gene function is crucial in V. cholerae.
Part of this work was presented at the International Symposium on Chemical Biology, Kolkata, India, 7–9 March 2007. 相似文献
12.
G. I. Naumov M. Yu. Shalamitskiy E. S. Naumova 《Doklady. Biochemistry and biophysics》2016,467(1):89-91
Using yeast genome databases and literature data, we have conducted a phylogenetic analysis of pectinase PGU genes from Saccharomyces strains assigned to the biological species S. arboricola, S. bayanus (var. uvarum), S. cariocanus, S. cerevisiae, S. kudriavzevii, S. mikatae, S. paradoxus, and hybrid taxon S. pastorianus (syn. S. carlsbergensis). Single PGU genes were observed in all Saccharomyces species, except S. bayanus. The superfamily of divergent PGU genes has been documented in S. bayanus var. uvarum for the first time. Chromosomal localization of new PGU1b, PGU2b, and PGU3b genes in the yeast S. bayanus var. uvarum has been determined by molecular karyotyping and Southern hybridization. 相似文献
13.
Cuadrado Y Fernández M Recio E Aparicio JF Martín JF 《Applied microbiology and biotechnology》2004,64(2):228-236
The first two genes of the threonine pathway, ask and asd, were cloned and sequenced from the aminoethoxyvinylglycine-producing Streptomyces sp. NRRL 5331. The two genes are organized in a bicistronic operon. ask, encoding the apartokinase (ASK), is located upstream from asd. The presence of a ribosome-binding site within the ask sequence suggests that this open reading frame encodes two overlapping proteins. The formation of both subunits of the aspartokinase from a single gene was studied using antibodies raised against the C-terminal end of the aspartokinase subunits. Disruption of asd results in a significant decrease of aminoethoxyvinylglycine production, thus supporting the involvement of the ask–asd operon in the biosynthesis of this metabolite. This is the first report in which a gene cluster for the first two steps of aminoethoxyvinylglycine biosynthesis is characterized.Abbreviations
ASD
Aspartate semialdehyde dehydrogenase
-
ASK
Aspartokinase
-
AVG
Aminoethoxyvinylglycine 相似文献
14.
Nadiawati Alias Nor Muhammad Mahadi Abdul Munir Abdul Murad Farah Diba Abu Bakar Nik Azmi Nik Mahmood Rosli Md Illias 《World journal of microbiology & biotechnology》2009,25(4):561-572
A gene encoding endochitinase from Trichoderma virens UKM-1 was cloned and expressed in E. coli BL21 (DE3). Both the endochitinase gene and its cDNA sequences were obtained. The endochitinase gene encodes 430 amino acids
from an open reading frame comprising of 1,690 bp nucleotide sequence with three introns. The endochitinase was expressed
as soluble and active enzyme at 20°C when induced with 1 mM IPTG. Maximum activity was observed at 4 h of post-induction time.
SDS-PAGE showed that the purified endochitinase exhibited a single band with molecular weight of 42 kDa. Biochemical characterization
of the enzyme displayed a near neutral pH characteristic with an optimum pH at 6.0 and optimum temperature at 50°C. The enzyme
is stable between pH 3.0–7.0 and is able to retain its activity from 30 to 60°C. The presence of Mg2+ and Ca2+ ions increased the enzyme activity up to 20%. The purified enzyme has a strong affinity towards colloidal chitin and low
effect on ethyl cellulose and D-cellubiose which are non-chitin related substrates. HPLC analysis from the chitin hydrolysis
showed the release of (GlcNAc)3, (GlcNAc)2 and GlcNAc, in which (GlcNAc)2 was the main product. 相似文献
15.
The reactions of isolates of Phytophthora cactorum, P. nicotianae and P. × pelgrandis to metalaxyl, mancozeb, dimethomorph, streptomycin and chloramphenicol were tested to obtain information about the variability of resistance in these pathogens. Distinct genetic groups showed significant differences in resistance to all tested substances except streptomycin. In response to streptomycin, the growth inhibition rates of distinct groups did not differ significantly. The most remarkable differences were detected in the reactions to chloramphenicol and metalaxyl. Discriminant analysis evaluating the effect of all substances confirmed the differences among the groups, which are in agreement with the differences revealed by earlier DNA analyses. 相似文献
16.
Chin-Hong Ng Soon-Leong Lee Kevin Kit-Siong Ng Norwati Muhammad Wickneswari Ratnam 《Journal of genetics》2009,88(1):25-31
The mating system and seed variation of Acacia hybrid (A. mangium × A. auriculiformis) were studied using allozymes and random amplified polymorphic DNA (RAPD) markers, respectively. Multi-locus outcrossing
rate estimations indicated that the hybrid was predominantly outcrossed (mean±s.e. t
m = 0.86±0.01). Seed variation was investigated using 35 polymorphic RAPD fragments. An analysis of molecular variance (AMOVA)
revealed the highest genetic variation among seeds within a pod (66%–70%), followed by among pods within inflorescence (29%–37%),
and the least variation among inflorescences within tree (<1%). In addition, two to four RAPD profiles could be detected among
seeds within pod. Therefore, the results suggest that a maximum of four seeds per pod could be sampled for the establishment
of a mapping population for further studies. 相似文献
17.
Chauhan N Negi MS Sabharwal V Khurana DK Lakshmikumaran M 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2004,108(5):951-957
Hybrids of Populus ciliata × maximowiczii are very vigorous and outperform both the parents in growth performance and yield. Genetic evaluation of 24 of these interspecific hybrids along with the two mother trees (Populus ciliata), and five male-parent (Populus maximowiczii) genotypes was carried out using the AFLP marker assay. Eight AFLP primer combinations detected 428 markers, of which 280 (66%) were polymorphic. Genetic relationships within the samples were evaluated by generating the similarity matrix based on Jaccards coefficient. The phenetic dendrograms, as well as the PCO plots, separated the hybrids and the two parent species into three distinct clusters. The hybrids grouped closer to the P. ciliata (female parent) cluster as compared to the P. maximowiczii (male parent) cluster. The hybrid cluster contained internal groupings, which correlated to some extent with growth performance. The four best performing hybrids (42m1, 65m1, 23m2, Cm2-5-20/91) formed a distinct sub-cluster. Data from a single primer combination was sufficient for distinguishing the hybrids from the parents and assigning paternity. The hybrids showed 22 markers that were absent in P. ciliata but were monomorphically present in all the hybrids, suggesting outcrossing and common paternity. Further, these 22 markers were found in all the P. maximowiczii genotypes confirming it as the male parent. These male-specific markers can be converted to SCAR markers and used for rapid screening of the P.ciliata × maximowiczii hybrids. The primer combination E-AAC × M-CAA was identified as most suitable for ascertaining true hybridity. AFLP proves to be a useful tool for screening of P. ciliata × maximowiczii hybrids at the early stages of development.Communicated by H.F. Liskens 相似文献
18.
Anna Szczerbakowa Justyna Tarwacka Michał Oskiera Henryka Jakuczun Bernard Wielgat 《Acta Physiologiae Plantarum》2010,32(5):867-873
Interspecific somatic hybrids between a diploid potato clone DG 81-68 susceptible to Phytophthora infestans (Mont.) de Bary and a resistant diploid tuber-bearing species Solanum × michoacanum were generated and analyzed. About 30 regenerants displaying an intermediate morphology were obtained as a result of three
separate PEG-mediated fusion experiments. The RAPD analysis confirmed the hybridity of all the regenerants. About 50% of the
hybrid plants exhibited vigorous growth and were stable in culture, while the rest of them rooted poorly and grew slowly in
vitro. Most of the hybrid clones were at the tetraploid level (70%), while 30% of the clones examined were at the hexaploid
level. The S. × michoacanum (+) DG 81-68 hybrids with growth anomalies were aneuploid. The variation in late blight resistance of the hybrid clones was
found in detached leaflet tests, with enhanced resistance characteristic for three tetraploid hybrids. 相似文献
19.
Four stereoisomers of 2-norbornyl-N–n-butylcarbamates are characterized as the pseudo substrate inhibitors of cholesterol esterase. Cholesterol esterase shows
enantioselective inhibition for enantiomers of exo- and endo-2-norbornyl-N–n-butylcarbamates. For the inhibitions by (R)-(+)- and (S)-(−)-exo-2-norbornyl-N–n-butylcarbamates, the R-enantiomer is 6.8 times more potent than the S-enantiomer. For the inhibitions by (R)-(+)- and (S)-(−)-endo-2-norbornyl-N–n-butyl-carbamates, the S-enantiomer is 4.6 times more potent than the R-enantiomer. The enzyme-inhibitor complex models have been proposed to explain these different enantioselectivities. 相似文献
20.
Akhilesh Kumar Amrita Chakraborty Srijani Ghanta Sharmila Chattopadhyay 《Plant Cell, Tissue and Organ Culture》2009,96(2):117-126
Morphologically identical transgenic mint (Mentha arvensis L.) with bacterial glutathione synthetase gene has been developed. Transformed plants were obtained by co-cultivation of
leaf disks with Agrobacterium tumefaciens strain LBA 4404 harbouring a binary vector pCAMBIA-CpGS that carried E. coli glutathione synthetase (GS), β-glucuronidase as reporter gene and nptII as selective marker gene for kanamycin resistance. Using a constitutive double CaMV 35S promoter and an rbcS transit peptide, we successfully addressed CpGS to the chloroplasts through pJIT 117 vector. Preculture and the presence of AS in the co-cultivation medium played a significant
role in enhancing transformation frequency. The highest transformation frequency was achieved with MS selection medium supplemented
with 25% coconut water, 1.12 mg l−1 BAP, 0.2 mg l−1 NAA, 50 mg l−1 kanamycin and 125 mg l−1 cefotaxime. Robust rooting of regenerated shoots was obtained in half-strength liquid MS medium containing 0.2 mg l−1 NAA and 50 mg l−1 kanamycin. The presence and expression of transgenes in transgenics (T0) was evidenced by GUS histoenzymatic assay, PCR and RT-PCR analysis of nptII and the gene of interest, i.e., GS of putative transgenic leaves. Chromosomal integration of GS gene was confirmed by Southern blot analysis. Transgenic plants were successfully acclimatized in the greenhouse. An overall
transformation frequency of 15% was achieved in approximately 3 months of time period. These results are discussed in relation
to heavy metal trafficking pathways in higher plants and to the interest of using plastid expression of PCS for biotechnological applications.
Akhilesh Kumar and Amrita Chakraborty contributed equally. 相似文献