共查询到20条相似文献,搜索用时 281 毫秒
1.
Lee JH Moon YH Kim N Kim YM Kang HK Jung JY Abada E Kang SS Kim D 《Biotechnology letters》2008,30(4):749-754
The gene encoding sucrose phosphorylase (742sp) in Leuconostoc mesenteroides NRRL B-742 was cloned and expressed in Escherichia coli. The nucleotide sequence of the transformed 742sp comprised an ORF of 1,458 bp giving a protein with calculated molecular mass of 55.3 kDa. 742SPase contains a C-terminal amino acid sequence that is significantly different from those of other Leu. mesenteroides SPases. The purified 742SPase had a specific activity of 1.8 U/mg with a K
m of 3 mM with sucrose as a substrate; optimum activity was at 37°C and pH 6.7. The purified 742SPase transferred the glucosyl
moiety of sucrose to cytosine monophosphate (CMP).
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
2.
Phosphoinositide-specific phospholipase C (PI-PLC) is an important enzyme, which is a key player involved in eukaryotic signal
transduction pathways. In plants, it plays a key role in growth and development as well as environmental stress. However,
little is known about its roles in signal transduction during sexual reproduction process. In this study, we cloned and characterized
a gene of full-length PI-PLC from ovules of Torenia fournieri, designated as TfPLC1. It was 2,171 bp in length, including an open reading frame encoding a polypeptide of 583 amino acids with molecular mass
of 66.02 kDa. The amino acid sequence deduced from the cDNA sequence shows 40–76% similarity to other plant PI-PLCs and contains
the characteristic X, Y and C2 domains. Northern blot analysis demonstrated it was predominantly expressed in ovules and flowers.
Furthermore, TfPLC1 promoter::GUS transgenic analysis indicated it specifically expressed in ovule, stigma and mature pollen grain. Immunohistochemical
staining showed that, in mature stigma, TfPLC1 protein was principally localized in the cells of stigmatic receptive surface.
Together, our data suggest that TfPLC1 may play an important role in plant sexual reproduction.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
3.
Nguyen VN Oh IJ Kim YJ Kim KY Kim YC Park RD 《Journal of industrial microbiology & biotechnology》2009,36(2):195-203
Two extracellular chitinases were purified from Paecilomyces variotii DG-3, a chitinase producer and a nematode egg-parasitic fungus, to homogeneity by DEAE Sephadex A-50 and Sephadex G-100 chromatography.
The purified enzymes were a monomer with an apparent molecular mass of 32 kDa (Chi32) and 46 kDa (Chi46), respectively, and
showed chitinase activity bands with 0.01% glycol chitin as a substrate after SDS-PAGE. The first 20 and 15 N-terminal amino
acid sequences of Chi32 and Chi46 were determined to be Asp-Pro-Typ-Gln-Thr-Asn-Val-Val-Tyr-Thr-Gly-Gln-Asp-Phe-Val-Ser-Pro-Asp-Leu-Phe
and Asp-Ala-X-X-Tyr-Arg-Ser-Val-Ala-Tyr-Phe-Val-Asn-Trp-Ala, respectively. Optimal temperature and pH of the Chi32 and Chi46
were found to be both 60°C, and 2.5 and 3.0, respectively. Chi32 was almost inhibited by metal ions Ag+ and Hg2+ while Chi46 by Hg2+ and Pb2+ at a 10 mM concentration but both enzymes were enhanced by 1 mM concentration of Co2+. On analyzing the hydrolyzates of chitin oligomers [(GlcNAc)
n
, n = 2–6)], it was considered that Chi32 degraded chitin oligomers as an exo-type chitinase while Chi46 as an endo-type chitinase. 相似文献
4.
Identification of Three <Emphasis Type="Italic">Superoxide dismutase</Emphasis> Genes from a <Emphasis Type="Italic">Geobacillus</Emphasis> sp. 总被引:1,自引:0,他引:1
We report the characterization of three Superoxide dismutase (sod) genes isolated from a bacterium in the Geobacillus genus. We isolated the bacterium from high-temperature pond mud and used 16S rRNA gene sequence to confirm its identity in
the Geobacillus genus. The three genes Mn-sod, Fe/Mn-sod, and Cu/Zn-sod were cloned and analyzed. Their open reading frames are Mn-sod: 615 bp encoding a 204 amino acid protein; Fe/Mn-sod: 1,236 bp encoding a 411 amino acid protein; Cu/Zn-sod: 522 bp encoding a 173 amino acid protein. When these sod genes were expressed in Escherichia coli, only Mn-SOD was able to be purified. The activity of the purified Mn-SOD we got was about 2,730 U/mg. Studies of this Mn-SOD
showed that it was thermostable at 60°, had 70% activity at 80° after 2.5 h, and still had 30% activity at 90° after 2.5 h.
Mn-SOD activity required the ion Mn2+. Based on gel electrophoresis, we deduced that this Mn-SOD was a homotetramer. No activity was detected after the other two
genes (Fe/Mn-sod, Cu/Zn-sod) were expressed in Escherichia coli, but activities were detected when expressed in Pichia pastoris. 相似文献
5.
Sanath Kumar Ammini Parvathi Ricardo L. Hernandez Kathleen M. Cadle Manuel F. Varela 《Archives of microbiology》2009,191(5):425-429
MurA [UDP-N-acetylglucosamine (UDP-NAG) enolpyruvyl transferase] is a key enzyme involved in bacterial cell wall peptidoglycan synthesis
and a target for the antimicrobial agent fosfomycin, a structural analog of the MurA substrate phosphoenol pyruvate. In this
study, we identified, cloned and sequenced a novel murA gene from an environmental isolate of Vibrio fischeri that is naturally resistant to fosfomycin. The fosfomycin resistance gene was isolated from a genomic DNA library of V. fischeri. An antimicrobial agent hypersensitive strain of Escherichia coli harboring murA from V. fischeri exhibited a high fosfomycin resistance phenotype, with minimum inhibitory concentration of 3,000 μg/ml. The cloned murA gene was 1,269 bp long encoding a 422 amino acid polypeptide with an estimated pI of 5.0. The deduced amino acid sequence
of the putative protein was identified as UDP-NAG enolpyruvyl transferase by homology comparison. The MurA protein with an
estimated molecular weight of 44.7 kDa was expressed in E. coli and purified by affinity chromatography. MurA of V. fischeri will be a useful target to identify potential inhibitors of fosfomycin resistance in pharmacological studies. 相似文献
6.
The extracellular lipase structural gene was isolated from cDNA of Aureobasidium pullulans HN2-3 by using SMARTTM RACE cDNA amplification kit. The gene had an open reading frame of 1245 bp long encoding a lipase. The coding region of the
gene was interrupted by only one intron (55 bp). It encodes 414 amino acid residues of a protein with a putative signal peptide
of 26 amino acids. The protein sequence deduced from the extracellular lipase structural gene contained the lipase consensus
sequence (G-X-S-X-G) and three conserved putative N-glycosylation sites. According to the phylogenetic tree of the lipases,
the lipase from A. pullulans was closely related to that from Aspergillus fumigatus (XP_750543) and Neosartorya fischeri (XP_001257768) and the identities were 50% and 52%, respectively. The mature peptide encoding cDNA was subcloned into pET-24a
(+) expression vector. The recombinant plasmid was expressed in Escherichia coli BL21(DE3). The expressed fusion protein was analyzed by SDS-PAGE and western blotting and a specific band with molecular
mass of about 47 kDa was found. Enzyme activity assay verified the recombinant protein as a lipase. A maximum activity of
0.96 U/mg was obtained from cellular extract of E. coli BL21(DE3) harboring pET-24a(+)LIP1. Optimal pH and temperature of the crude recombinant lipase were 8.0 and 35 °C, respectively and the crude recombinant lipase
had the highest hydrolytic activity towards peanut oil. 相似文献
7.
The extracellular inulinase structural gene was isolated from the genomic DNA of the marine yeast Pichia guilliermondii strain 1 by PCR. The gene had an open reading frame of 1,542 bp long encoding an inulinase. The coding region of the gene
was not interrupted by any intron. It encoded 514 amino acid residues of a protein with a putative signal peptide of 18 amino
acids and the calculated molecular mass of 58.04 kDa. The protein sequence deduced from the inulinase structural gene contained
the inulinase consensus sequences (WMNXPNGL) and (RDPKVF). It also had ten conserved putative N-glycosylation sites. The inulinase from P. guilliermondii strain 1 was found to be closely related to that from Kluyveromyces marxianus. The inulinase gene without the signal sequence was subcloned into pPICZαA expression vector and expressed in Pichia pastoris X-33. The expressed fusion protein was analyzed by SDS-PAGE and western blotting and a specific band with molecular mass
of about 60 kDa was found. Enzyme activity assay verified the recombinant protein as an inulinase. A maximum activity of 58.7 ± 0.12 U/ml
was obtained from the culture supernatant of P. pastoris X-33 harboring the inulinase gene. A large amount of monosaccharides, disaccharides and oligosaccharides were detected after
the hydrolysis of inulin with the crude recombinant inulinase. 相似文献
8.
Kemel Jellouli Ali Bougatef Laila Manni Rym Agrebi Rayda Siala Islem Younes Moncef Nasri 《Journal of industrial microbiology & biotechnology》2009,36(7):939-948
A protease-producing bacterium was isolated from an alkaline wastewater of the soap industry and identified as Vibrio metschnikovii J1 on the basis of the 16S rRNA gene sequencing and biochemical properties. The strain was found to over-produce proteases
when it was grown at 30°C in media containing casein as carbon source (14,000 U ml−1). J1 enzyme, the major protease produced by V. metschnikovii J1, was purified by a three-step procedure, with a 2.1-fold increase in specific activity and 33.3% recovery. The molecular
weight of the purified protease was estimated to be 30 kDa by SDS-PAGE and gel filtration. The N-terminal amino acid sequence
of the first 20 amino acids of the purified J1 protease was AQQTPYGIRMVQADQLSDVY. The enzyme was highly active over a wide
range of pH from 9.0 to 12.0, with an optimum at pH 11.0. The optimum temperature for the purified enzyme was 60°C. The activity
of the enzyme was totally lost in the presence of PMSF, suggesting that the purified enzyme is a serine protease. The kinetic
constants K
m and K
cat of the purified enzyme using N-succinyl-l-Ala-l-Ala-l-Pro-l-Phe-p-nitroanilide were 0.158 mM and 1.14 × 105 min−1, respectively. The catalytic efficiency (K
cat
/K
m) was 7.23 × 108 min−1 M−1. The enzyme showed extreme stability toward non-ionic surfactants and oxidizing agents. In addition, it showed high stability
and compatibility with some commercial liquid and solid detergents. The aprJ1 gene, which encodes the alkaline protease from V. metschnikovii J1, was isolated, and its DNA sequence was determined. The deduced amino acid sequence of the preproenzyme differs from that
of V. metschnikovii RH530 detergent-stable protease by 12 amino acids, 7 located in the propeptide and 5 in the mature enzyme. 相似文献
9.
A novel antifreeze protein cDNA was cloned by RT-PCR from the larva of the yellow mealworm Tenebrio molitor. The coding fragment of 339 bp encodes a protein of 112 amino acid residues and was fused to the expression vectors pET32a
and pTWIN1. The resulted expression plasmids were transformed into Escherischia coli strains BL21 (DE3), ER2566, and Origami B (DE3), respectively. Several strategies were used for expression of the highly
disulfide-bonded β-helix-contained protein with the activity of antifreeze in different expression systems. A protocol for
production of refolded and active T. molitor antifreeze protein in bacteria was obtained. 相似文献
10.
Jing-Wei Lin Li-Xia Hao Gui-Xue Xu Fei Sun Feng Gao Ren Zhang Li-Xia Liu 《World journal of microbiology & biotechnology》2009,25(3):383-390
The fungal immunomodulatory proteins (FIPs) are a new protein family identified from several edible and medical mushrooms
and play an important role in anti-tumor, anti-allergy and immunomodulating activities. A gene encoding the FIP was cloned
from the mycelia of Changbai Lingzhi (Ganoderma lucidum) and recombinant expressed in the Pichia pastoris expression system. SDS-PAGE, amino acid composition and circular dichroism analyses of the recombinant FIP (reFIP) indicated
that the gene was correctly and successfully expressed. In vitro assays of biological activities revealed that the reFIP exhibited
similar immunomodulating capacities as native FIPs. The reFIP significantly stimulated the proliferation of mouse spleen lymphocytes
and apparently enhanced the expression level of interleukin-2 released from the mouse splenocytes. In addition, anti-tumor
activity assay showed that the reFIP could inhibit the proliferation of human leukemia-NB4 by inducing the cell apoptosis
to a degree of about 32.4%. Taken together, the FIP gene from Changbai G.
lucidum has been integrated into the yeast genome and expressed effectively at a high level (about 191.2 mg l−1). The reFIP possessed very similar biological activities to native FIPs, suggesting its potential application as a food supplement
or immunomodulating agent in pharmaceuticals and even medical studies.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
11.
Sumita Kumari Prabhjeet Singh Sneh L. Singla-Pareek Ashwani Pareek 《Molecular biotechnology》2009,42(2):195-204
12.
The purpose of this research is to identify the probable mitochondrial factor associated with cytoplasmic male sterility (cms)
by comparative analysis of cms and its isogenic maintainer lines in stem mustards. Dramatic variations in the morphology of
floral organs were observed in cms stem mustard. Mitochondrial atpA gene was shown to be altered in cms compared with that in its maintainer line, of which mitochondrial atpA gene from its maintainer line was sequenced to encode 507 amino acids. It was indicative of high homology with mitochondrial
atpA genes from other species, even as high as 94% in similarity with Oryza sativa in terms of amino acid constituents. However, only 429 amino acids were deduced in cms showing 83% similarity with atpA gene from its maintainer line. Two copies were observed in its maintainer line, but only one was found in cms. Such numerous
differences of mitochondrial atpA gene between cms and its maintainer lines may not be the results of evolutionary divergence but the rearrangements of mitochondria.
Expression of mitochondrial atpA gene was shown to be down-regulated in cms by using Northern blot. Consequently, mitochondrial ATP synthesis was severely
decreased more than one fold in cms stem mustard indicating deficiency in mitochondrial ATP synthesis in this type of cms.
Therefore, we deduced that mitochondrial atpA gene altered in cms could be associated with male-sterility in this type of cms.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Jing-Hua Yang and Yan Huai contributed equally to this work. 相似文献
13.
Stefanie Kimbacher Ingrid Gerstl Branko Velimirov Sylvia Hagemann 《Molecular genetics and genomics : MGG》2009,282(2):165-172
P transposons belong to the eukaryotic DNA transposons, which are transposed by a cut and paste mechanism using a P-element-coded transposase. They have been detected in Drosophila, and reside as single copies and stable homologous sequences in many vertebrate species. We present the P elements Pcin1, Pcin2 and Pcin3 from Ciona intestinalis, a species of the most primitive chordates, and compare them with those from Ciona savignyi. They showed typical DNA transposon structures, namely terminal inverted repeats and target site duplications. The coding
region of Pcin1 consisted of 13 small exons that could be translated into a P-transposon-homologous protein. C. intestinalis and C. savignyi displayed nearly the same phenotype. However, their P elements were highly divergent and the assumed P transposase from C. intestinalis was more closely related to the transposase from Drosophila melanogaster than to the transposase of C. savignyi. The present study showed that P elements with typical features of transposable DNA elements may be found already at the base of the chordate lineage.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
14.
Avidan O Kaltageser E Pechatnikov I Wexler HM Shainskaya A Nitzan Y 《Archives of microbiology》2008,190(6):641-650
The outer membrane proteins of Desulfovibrio piger and Bilophila wadsworthia (Omp-DP and Omp-BW, respectively) and the genes encoding them (omp-DP and omp-BW) were isolated and characterized. Native Omp-DP and Omp-BW form a trimeric structure of approximately 120 kDa. These proteins
disaggregated into monomers with a molecular weight of approximately 53 kDa after heating at 95°C for 10 min. The pore-forming
abilities of these oligomeric proteins demonstrated that they form small nonspecific channels with an exclusion limit of 260–300 Da.
The omp-DP and omp-BW genes were cloned and sequenced. Sequence analyses revealed an open reading frame of 1,512 bp for omp-DP and 1,440 bp for omp-BW. The mature Omp-DP protein consisted of 480 amino acids and had a calculated MW of 53,290 Da. The mature Omp-BW protein consisted
of 456 amino acids and had a calculated MW of 50.050 Da. Alignment of Omp-DP with Omp-BW revealed 54% homology, whereas alignment
with other known porins showed a low level of homology. Analysis of the secondary structures indicated that both proteins
span the outer membrane 18 times with amphipathic β-strands. This research presents porins which were isolated and characterized
for the first time from bacteria belonging to the Desulfovibrionaceae family.
O. Avidan and E. Kaltageser have contributed equally to this work. 相似文献
15.
A potent fibrinolytic enzyme-producing bacterium was isolated from the traditional Korean condiment Chungkook-jang and identified
as Bacillus vallismortis Ace02. The extracellular fibrinolytic enzyme was purified with a 18% recovery of activity from supernatant cultures using
CM-Sepharose column chromatography and Sephacryl S-200 gel filtration. The specific activity of the purified enzyme was 757 kFU mg−1. Its molecular mass was about 28 kDa and the initial amino acids of the N-terminal sequence were AQSVPYGVSQ. The full amino acid sequence of fibrinolytic enzyme Ace02 corresponded with bacteriolytic
enzyme, L27, from Bacillus licheniformis, which has strong lytic activity against Streptococcus mutans, a major causative strain of dental caries. This suggests that the purified enzyme should be used for prevention of dental
caries as well as being an effective thrombolytic agent. 相似文献
16.
Katsuyuki Kakeda 《Plant cell reports》2009,28(9):1453-1460
Diploid Hordeum bulbosum (a wild relative of cultivated barley) exhibits a two-locus self-incompatibility (SI) system gametophytically controlled
by the unlinked multiallelic loci S and Z. This unique SI system is observed in the grasses (Poaceae) including the tribe Triticeae. This paper describes the identification
and characterization of two F-box genes cosegregating with the S locus in H. bulbosum, named Hordeum
S locus-linked F-box 1 (HSLF1) and HSLF2, which were derived from an S
3 haplotype-specific clone (HAS175) obtained by previous AMF (AFLP-based mRNA fingerprinting) analysis. Sequence analysis showed
that both genes encode similar F-box proteins with a C-terminal leucine-rich repeat (LRR) domain, which are distinct from
S locus (or S haplotype-specific) F-box protein (SLF/SFB), a class of F-box proteins identified as the pollen S determinant in S-RNase-based gametophytic SI systems. A number of homologous F-box genes with an LRR domain were found in
the rice genome, although the functions of the gene family are unknown. One allele of the HSLF1 gene (HSLF1-S
3) was expressed specifically in mature anthers, whereas no expression was detected from the other two alleles examined. Although
the degree of sequence polymorphism among the three HSLF1 alleles was low, a frameshift mutation was found in one of the unexpressed alleles. The HSLF2 gene showed a low level of expression with no tissue specificity as well as little sequence polymorphism among the three
alleles. The multiplicity of S locus-linked F-box genes is discussed in comparison with those found in the S-RNase-based SI system.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession numbers AB511822–AB511825
and AB511859–AB511862. 相似文献
17.
A genetic transformation system has been developed for callus cells of Crataegus
aronia using Agrobacterium
tumefaciens. Callus culture was established from internodal stem segments incubated on Murashige and Skoog (MS) medium supplemented with
5 mg l−1 Indole-3-butyric acid (IBA) and 0.5 mg l−1 6-benzyladenine (BA). In order to optimize the callus culture system with respect to callus growth and coloration, different
types and concentrations of plant growth regulators were tested. Results indicated that the best average fresh weight of red
colored callus was obtained on MS medium supplemented with 2 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.5 mg l−1 kinetin (Kin) (callus maintenance medium). Callus cells were co-cultivated with Agrobacterium harboring the binary plasmid pCAMBIA1302 carrying the mgfp5 and hygromycin phosphotransferase (hptII) genes conferring green fluorescent protein (GFP) activity and hygromycin resistance, respectively. Putative transgenic calli
were obtained 4 weeks after incubation of the co-cultivated explants onto maintenance medium supplemented with 50 mg l−1 hygromycin. Molecular analysis confirmed the integration of the transgenes in transformed callus. To our knowledge, this
is the first time to report an Agrobacterium-mediated transformation system in Crataegus
aronia. 相似文献
18.
Erkang Yin Yilin Le Jianjun Pei Weilan Shao Qiyin Yang 《World journal of microbiology & biotechnology》2008,24(2):275-280
According to the amino acid sequence, a codon-optimized xylanase gene (xynA1) from Thermomyces lanuginosus DSM 5826 was synthesized to construct the expression vector pHsh-xynA1. After optimization of the mRNA secondary structure in the translational initiation region of pHsh-xynA1, free energy of the 70 nt was changed from −6.56 to −4.96 cal/mol, and the spacing between AUG and the Shine-Dalgarno sequence
was decreased from 15 to 8 nt. The expression level was increased from 1.3 to 13% of total cell protein. A maximum xylanase
activity of 47.1 U/mL was obtained from cellular extract. The recombinant enzyme was purified 21.5-fold from the cellular
extract of Escherichia coli by heat treatment, DEAE-Sepharose FF column and t-Butyl-HIC column. The optimal temperature and pH were 65 °C and pH 6.0,
respectively. The purified enzyme was stable for 30 min over the pH range of 5.0–8.0 at 60 °C, and had a half-life of 3 h
at 65 °C. 相似文献
19.
20.
Amend JP Meyer-Dombard DR Sheth SN Zolotova N Amend AC 《Archives of microbiology》2003,179(6):394-401
The soluble periplasmic subunit of the formate dehydrogenase FdhA of the tetrachloroethene-reducing anaerobe Sulfurospirillum multivorans was purified to apparent homogeneity and the gene (fdhA) was identified and sequenced. The purified enzyme catalyzed the oxidation of formate with oxidized methyl viologen as electron acceptor at a specific activity of 1683 nkat/mg protein. The apparent molecular mass of the native enzyme was determined by gel filtration to be about 100 kDa, which was confirmed by the fdhA nucleotide sequence. fdhA encodes for a pre-protein that differs from the truncated mature protein by an N-terminal 35-amino-acid signal peptide containing a twin arginine motif. The amino acid sequence of FdhA revealed high sequence similarities to the larger subunits of the formate dehydrogenases of Campylobacter jejuni, Wolinella succinogenes, Escherichia coli (FdhN, FdhH, FdhO), and Methanobacterium formicicum. According to the nucleotide sequence, FdhA harbors one Fe4/S4 cluster and a selenocysteine residue as well as conserved amino acids thought to be involved in the binding of a molybdopterin guanidine dinucleotide cofactor.Abbreviations
Fdh
Formate dehydrogenase
-
PCE
Tetrachloroethene 相似文献