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1.
W Basuki M Iizuka K Ito K Furuichi N Minamiura 《Bioscience, biotechnology, and biochemistry》1992,56(2):180-185
Glucose isomerase from Streptomyces phaeochromogenes was purified from a commercial preparation, Swetase, by DEAE-cellulose, Bio-Gel A-0.5 m, and hydroxyapatite column chromatographies. It was found to be 2 fractions; F-A, not adsorbed on hydroxyapatite and F-B, adsorbed on hydroxyapatite. They were homogeneous in ordinary and SDS-PAGE and had similarities in some enzymatic and physico-chemical properties. The differences, however, were found in the N-terminal amino acid, which was only serine for F-A while it was serine and alanine for F-B, and also in their peptide mapping patterns of digests with trypsin, Achromobacter protease I, and cyanogen bromide. The results suggest that glucose isomerase from S. phaeochromogenes was composed of the two kinds of isozymes and that each of isozymes was a tetramer constituted of non-identical subunits. 相似文献
2.
Summary Characteristics of Streptomyces phaeochromogenes cells immobilized by radiation-induced polymerization of 2-hydroxyethyl methacrylate at low temperatures were studied. It was found that very high concentrations of cells could be trapped effectively on the surface of the polymer matrix. Glucose isomerase activity of immobilized cells increased with increasing cell concentration. No cell leakage from the matrix was observed with repeated use, even at very high cell concentration and low monomer concentrations. The Km value of immobilized cells decreased with increasing cell concentration and with decreasing monomer concentration; it was close to that of intact cells. 相似文献
3.
Summary The glucose isomerase activity ofStreptomyces haeochromogenes strains 1 and 2 varies considerably with the assay conditions (pH, glucose concentration,etc.). Nine other species of streptomyces were tested under conditions optimal forS.phaeochromogenes 2. The highest enzyme activity was found inS.nigrificans 3014. 相似文献
4.
Summary The isomerization of D-glucose in mixed ethanol-water was studied at various reaction temperatures (40–70 °C), employing glucose isomerase fromStreptomyces phaeochromogenes andClostridium thermohydrosulfuricum, respectively. The thermophilicClostridium enzyme was considerably, more stable towards the combination of organic cosolvent and increased temperature and with this enzyme a 55% yield of fructose from glucose was obtained at relatively low concentration of ethanol (40 %). 相似文献
5.
Immobilization of Glucose Isomerase-Containing Streptomyces phaeochromogenes Cells in Fine-Particle Form
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A new preparation method for immobilizing Streptomyces phaeochromogenes cells in fine-particle form was investigated using radiation-induced polymerization at low temperatures with previously salted out hydrophilic monomers. Using this method, it was found that the glucose isomerase activity of the immobilized cell particles was markedly higher than that of immobilized cells in block form obtained without salting out of the monomer. The diameter of the particles was varied by changing the irradiation temperature or the concentrations of monomer and salt. The magnitude of the enzymatic activity increased with decreasing particle diameter. Km values of the immobilized cell particles were close to that of the intact cell. These facts suggested that the cells were trapped on the surface of the particle. 相似文献
6.
Goldring A. Zamir D. Degani Ch. 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1985,71(3):491-494
Summary Avocado (Persea americana) cultivars were assayed for phosphoglucose isomerase (PGI) isozymes using starch gel electrophoresis. Three PGI genes were identified: one monomorphic locus, Pgi-I, coding for the plastid isozyme and two independently assorting loci, Pgi-2 and Pgi-3, coding for the cytosolic isozymes. The genetic analysis was based on comparisons of PGI zymograms from somatic and pollen tissue and on Mendelian analysis of progeny from selfed trees. The isozymic variability for PGI can be used for cultivar identification and for differentiating between hybrid and selfed progeny in avocado breeding. 相似文献
7.
The isozyme patterns of glucose-6-phosphate isomerase (GPI) have been analyzed in ten species of polychaetes of the genera
Polydora and Dipolydora (Polychaeta: Spionidae). The GPI patterns of these species have been found to have some specific characteristics that cannot
be explained in terms of the generally accepted views on the nature of isozymes. The patterns are represented by two hybridizing
isozymes with different expression specificities that exhibit coordinated allozymic variation in most individuals of each
species studied. Involvement of alternative splicing in the expression of the GPI gene is considered to be the most probable
mechanism of the formation of the unusual GPI isozyme patterns in polydorids. 相似文献
8.
Tetsukazu Yahara Takayuki Kawahara Daniel J. Crawford Motomi Ito Kuniaki Watanabe 《American journal of botany》1989,76(8):1247-1253
An electrophoretic study of isozyme number for seven soluble enzymes revealed extensive gene duplications in eight diploid species of American Eupatorium belonging to three morphological groups. The enzymes isocitrate dehydrogenase, phosphoglucomutase, phosphoglucose isomerase, 6-phosphogluconate dehydrogenase, and shikimate dehydrogenase occur as three to six isozymes in all species, whereas the minimal conserved number typical of diploid plants is two isozymes for each. Fructose 1, 6-biphosphate aldolase is expressed as multibanded pattern suggesting fixed heterozygosity in all examined species. It was not possible to document gene duplication for triosephosphate isomerase from the electrophoretic patterns. All species examined have a chromosome number of 2n = 20, which has been regarded as the basic diploid number for Eupatorium. However, the detection of extensive duplications suggests that 2n = 10 may be the original diploid chromosome number in Eupatorium and that plants with 2n = 20 are of polyploid origin. This hypothesis would mean that extensive duplications at isozyme gene loci have been maintained since the origin of the genus, despite chromosomal diploidization having occurred. 相似文献
9.
The composition, molecular weight and in vitro antioxidant activity of various sulfated polysaccharides obtained by anion
exchange chromatography, acid hydrolysis and radical process degradation of the crude sulfated polysaccharide extracted from
Laminaria japonica were compared. The low sulfated F-A2, with a peak-molecular weight (Mp) of 5–15 kDa, 14.5% sulfated ester and 21.8% glucuronic
acid, exhibited a very strong antioxidant activity on superoxide and hydroxyl radicals, with activity even higher than that
of large molecular weight fractions F-A and F-B. However, highly sulfated fractions with a peak-molecular weight below 15 kDa
had much lower antioxidant activities than other fractions. These results indicated that the sulfate group of the low molecular
weight fractions represents a physical block for the reaction with oxygen radicals. The chemical properties and antioxidant
activities of sulfated polysaccharide fractions obtained by radical process degradation of crude sulfated polysaccharide were
quite different from those obtained by acid hydrolysates. By radical process degradation, the high molecular weight was decreased
to give LM2 (Mp 8 kDa) and LM1 (Mp 1.5 kDa), with a yield of 40% and 15%, respectively. LM2 was enriched with fucose and sulfated
ester, while containing low amounts of glucuronic acid. The antioxidant activity showed that LM2 was unable to scavenge either
superoxide or hydroxyl radical, which suggested that radical process degradation targeted mainly ascopyllan-like species rich
in glucuronic acid, while the fraction rich in sulfated l-fucose remained unchanged. However, LM1 with Mp 1.5 kDa still retained apparent scavenging ability for superoxide radical,
although it contained no glucuronic acid and certain amounts of galactose and mannose as main neutral sugars. These result
suggest that the antioxidant activity of sulfated polysaccharides is apparently related not only to molecular weight and sulfated
ester content, as previously determined, but also to glucuronic acid and fucose content. 相似文献
10.
Stephen R. Palumbi Bruce D. Sidell Rebecca Van Beneden Glenn D. Smith Dennis A. Powers 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1980,138(1):49-57
Summary In order to evaluate the role of glucose-phosphate isomerase (GPI) inFundulus heteroclitus, the isozymes and allozymes were purified and some of their physical and kinetic properties determined.Isozymes were purified from both liver (GPI-B) and muscle (GPI-A) tissue (Tables 1, 2). Gel filtration of the native enzyme and SDS-polyacrylamide gel electrophoresis indicated that all forms are dimers of approximately 110,000 Daltons (Figs. 4, 5). Although thermal stability studies revealed no differences between the allozymes, the isozymes were clearly different (Figs. 6, 7). Kinetic analysis showed further differences between isozymes inK
m for substrate andK
I for 6-phosphogluconate (Figs. 8, 9; Table 3). No significant differences were found between the allozymes of the B-locus under the conditions employed in this study.Based on the tissue specificities and the functional differences between isozymes, we propose a possible regulatory role for GPI-B inF. heteroclitus. The sensitivity of this isozyme to 6-phosphogluconate inhibition may allow GPI-B to act as a regulatory enzyme in the partitioning of carbon flow between glycolysis and the hexose monophosphate shunt.Abbreviations me
-mercaptoethanol
-
F6P
fructose-6-phosphate
-
G1P
glucose-1-phosphate
-
G6P
glucose-6-phosphate
-
G6Pase
glucose-6-phosphatase
-
G6PDH
glucose-6-phosphate dehydrogenase
-
GPI
glucosephosphate isomerase
-
HK
hexokinase
-
HMP
hexose monophosphate shunt
-
6PG
6-phosphogluconate
-
PGM
phosphoglucomutase
Supported in part by: NSF grants DEB-76-19877 to D.A.P. and PCM 77-16838 to B.D.S., NIH Biomedical grant 5-50-7RR07-041 and a grant from the National Geographic Society. G.D.S. and R.V.B. are NIH trainees supported by a training grant (No. HD00139) to the Department of Biology, The Johns Hopkins University. This is contribution No. 1052 from the Department of Biology 相似文献
11.
Chemical characters and antioxidative properties of sulfated polysaccharides from Laminaria japonica
Chang-Hu Xue Yu Fang Hong Lin Lei Chen Zhao-Jie Li Deng Deng Chong-Xiao Lu 《Journal of applied phycology》2001,13(1):67-70
A low molecular weight sulfated polysaccharide (L-A) was prepared bymild acid hydrolysis of crude fucoidan (F-A) from Laminaria japonica. In comparison with F-A, L-A had a lower proportion of fucose residues,but a similar proportion of sulfate. The galactose content of both fractionswas relatively high, especially for L-A (57%). The antioxidant propertiesof the two polysaccharides were studied using two low-density lipoproteinoxidation systems. L-A had a stronger effect against low-density lipoproteinoxidation in both systems. F-A inhibited the AAPH-induced low-densitylipoprotein oxidation, but had little effect on the Cu++-inducedsystem due to its large molecular mass. The active sulfated fraction L-A,containing galactose, mannose and fucose (about 9: 2: 2) is reported herefor the first time. 相似文献
12.
C. Benito A. M. Figueiras M. T. González-Jaén 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,73(4):581-588
Summary Zymogram analysis was used to identify the Aegilops umbellulata chromosomes that carry the structural genes for particular isozymes. Wheat, Aegilops and wheat-Aegilops hybrid derivative lines (which contained identified Aegilops chromosomes) were tested by gel electrophoresis for isozymes of particular enzymes. It was found that Aegilops chromosome A (nomenclature according to G. Kimber 1967) carries a structural gene for 6-phosphogluconate dehydrogenase, Aegilops chromosome B carries structural genes for glucose phosphate isomerase and phosphoglucose mutase, Aegilops chromosome D carries genes for leaf peroxidases, Aegilops chromosome E carries structural genes for endosperm peroxidases, acid phosphatases and leaf esterases, Aegilops chromosome F carries a gene for embryo plus scutellum peroxidases and Aegilops chromosome G carries structural genes for endosperm alkaline phosphatases, leaf alkaline phosphatases and leaf esterases. The results obtained indicate that chromosome B is partially homoeologous of the wheat chromosomes of group 1 and 4, and chromosome E is partially homoeologous of wheat chromosomes of groups 7 and 4. Circumstantial evidence is also provided about the possible association between chromosomes C, D and A of A. umbellulata respectively with chromosomes 5, 2 and 1 of wheat. 相似文献
13.
Dissociation, reassociation, and purification of plastid and cytosolic phosphoglucose isomerase isozymes 总被引:7,自引:4,他引:3
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The plastid and cytosolic isozymes of the dimeric enzyme phosphoglucose isomerase (EC 5.3.1.9) from spinach (Spinacia oleracea) and cauliflower (Brassica oleracea) were purified to apparent homogeneity. The isozymes from sunflower (Helianthus annuus) and Clarkia xantiana were partially purified. When subunits from two electrophoretically distinguishable cytosolic isozymes, either from the same or from different species, were dissociated and allowed to reassociate in each other's presence, an active hybrid enzyme, consisting of one subunit of each type, was formed in addition to the two original homodimers. Active hybrid enzymes were also formed by dissociation and reassociation of plastid isozymes. Hybrid molecules were not produced between the plastid and cytosolic subunits, suggesting that they are not able to bind with each other. Additional differences between the plastid and cytosolic isozymes are described. 相似文献
14.
The date palm (Phoenix dactylifera L.) is a long-lived, dioecious, arborescent monocotyledon which must be propagated vegetatively by offshoots to maintain clones. An extensive breeding program begun in 1948 at Indio, California, to obtain superior lines has resulted in the production of several seedling populations of known parents. These were used to study the genetic control of isozymes of alcohol dehydrogenase, esterase, glutamate oxaloacetate transaminase, phosphoglucose isomerase and phosphoglucose mutase from leaf tissue. The five enzyme systems are specified by seven polymorphic genes with 14 alleles. Additional polymorphism was found in two other species of Phoenix. Twenty-six female and 20 male date palm cvs. were genotyped to provide, insofar as is known, the first single-gene markers for the date palm and perhaps for any arborescent monocotyledon. 相似文献
15.
Summary A simple and unique procedure was developed to purify phosphoglucose isomerase variants from the whole mouse body extracts and Drosophila homogenate. It involved the use of an 8-(6-aminohexyl)-amino-ATP-Sepharose column followed by a preparative isoelectric focusing. In each case, the enzyme in the homogenate was adsorbed by ionic interaction on the ATP-Sepharose column. Substantial purification was achieved by the affinity elution with the substrate-glucose-6-phosphate. Mouse and Drosophila phosphoglucose isomerase as well as the corresponding variants were shown to be dimers of similar molecular weight and to exhibit similar kinetic properties. The isoelectric points for the variants from DBA/2J and C57BL/6J mice were determined to be 8.4 and 8.7 respectively, while they were 6.8 and 6.3 respectively for Drosophila and 4/4 variants. Differential thermal stability was observed for the two mouse variants but not for the Drosophila ones. Amino acid composition analysis was performed for both mouse and Drosophila enzymes. Rabbit antisera for mouse (DBA/2J) and Drosophila (2/2) enzymes were raised. Within each species, complete immunological identity was observed between the variants. The antisera were used to characterize the null mutants of phosphoglucose isomerase identified in the mouse and Drosophila populations. By rocket immunoelectrophoresis, the null allele of the naturally occurring heterozygous null variant of Drosophila was shown to express no cross-reacting materials (CRM). 相似文献
16.
Daniel J. Crawford Edwin B. Smith Marvin L. Roberts Maryan Benkowski Melinda Hoffman 《American journal of botany》1990,77(1):54-63
Enzyme electrophoresis was employed to ascertain the number of loci encoding plastid phosphoglucose isomerase (PGI) in species representing all sections of North American Coreopsis. Several species from each of the closely related genera Bidens, Coreocarpus, Cosmos, and Thelesperma were also examined. Species in nine of the 11 sections of North American Coreopsis have two isozymes for plastid PGI, and nearly all species examined in the four other genera also have two (one species has three) isozymes. Since most diploid vascular plants have one plastid PGI isozyme, a gene duplication probably occurred in an ancestor that is common to Coreopsis and the other four genera. That is, two isozymes represent the ancestral number for Coreopsis. The two sections (Electra and Anathysana) apparently lacking the duplication are closely related woody plants restricted largely to Mexico. One gene encoding plastid PGI ostensibly was silenced in a common ancestor of these two sections. This is concordant with other data suggesting a close relationship between the two sections, i.e., they appear to represent a monophyletic group. The electrophoretic data also indicate that 1) the enigmatic monotypic section Silphidium is more closely related to eastern North American sections and not derived from section Electra; and 2) section Anathysana is not ancestral to the three California sections Leptosyne, Pugiopappus, and Tuckermannia; rather, it represents a terminal element closely related to and possibly derived from section Electra. 相似文献
17.
The genetic control of isozymes from Citrus and its near relatives was determined for three gene/enzyme systems: glutamate oxaloacetate transaminase, phosphoglucose isomerase and phosphoglucose mutase. These enzymes are controlled by four genes having 19 codominant alleles, 12 of which occur in Citrus subg Citrus. Formal genetic studies were carried out with F, biotypes and F1 populations of known origin. When biotypes were grouped into traditionally recognized species to examine genetic affinities within and between species, a remarkable pattern of uniformity of genotype combinations was found within a species, and every species had an unique combination. Because many economically important cultivars produce asexual(nucellar) as well as sexual(zygotic) embryos, a central problem of the breeder is to distinguish these when plants are young, long before fruiting. Isozyme markers can be used with varying degrees of efficiency, depending on the genotypes of the particular parents, to distinguish nucellar seedlings from those of zygotic origin. 相似文献
18.
Saliva is known to modulate the adhesion of bacteria in the oral cavity. The present work was performed to assess the effect
of salivary components on the adhesion of Escherichia coli to a model oral surface. Several genetically engineered E. coli strains were used to examine the role of type 1 fimbriation in the interaction of these strains with salivary components
in solution or adsorbed to hydroxyapatite. High (MG1) and low (MG2) molecular weight salivary mucins, and secretory immunoglobulin
A (sIgA), were found to interact with the surface of E. coli, and these interactions were independent of the expression of fimbriae or capsule. In contrast, fimbriated strains of E. coli adhered to a greater extent to saliva-coated synthetic hydroxyapatite (HAP) than did nonfimbriated strains. Testing of salivary
components separated by gel filtration chromatography revealed that only high-molecular-weight components promoted adhesion
of E. coli to HAP. Additional studies found that purified MG2 and sIgA promoted the adhesion of E. coli to HAP. Expression of type 1 fimbriae enhanced adhesion, while mannose inhibited adhesion of fimbriated strains, to saliva-coated
HAP and to HAP coated with MG2 and sIgA. We conclude that salivary MG2 and sIgA may provide receptors for the adhesion of
type 1 fimbriated E. coli to oral surfaces.
Received: 10 February 1996 / Accepted: 11 March 1996 相似文献
19.
Summary Four electrophoretic variants of human erythrocyte triosephosphate isomerase (TPI) have been studied to investigate the origin of the multiple forms of human TPI, in particular the constitutive TPI-B isozyme and the cell division-associated TPI-A isozyme. The variant phenotype expressed by the constitutive TPI-B isozyme in both erythrocytes and peripheral lymphocytes was also expressed by the cell division-associated isozymes in mitogen-stimulated lymphocytes and hair root cells. These results strongly support the hypothesis of Decker and Mohrenweiser (1981) that TPI-B and TPI-A originated from the same structural gene. We also found that the isozyme e is different from TPI-A with respect to both its electrophoretic mobility and heat stability. This finding is in contrast to the recent conclusion of Yuan et al. (1981) that both the isozyme e and TPI-A are deamidation products of TPI-B. 相似文献
20.
H. G. Vartak M. C. Srinivasan V. K. Powar M. V. Rele J. M. Khire 《Biotechnology letters》1984,6(8):493-494
Summary Specific glucose and xylose isomerases have been identified in cell-free culture filtrates of a Chainia species. Treatment with DEAE-cellulose selectively adsorbed xylose isomerase activity while only the glucose isomerase was adsorbed on CM-cellulose. Glucose isomerase was completely inhibited by xylose at 1.3 × 10-4 M concentration. The differential identity of the extracellular glucose and xylose isomerases, unique to Chainia, is discussed.(NCL Communication 3562) 相似文献