• Microbiology and Biotechnology Letters
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• v.8 no.2
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• pp.125-133
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• 1980

A microorganism which produced D-glucose isomerase was identified to be similar to Streptomyces antibioticus on the morphological, cultural and physiological characteristics except the spore chain and the utilization of sucrose. D-xylose grown cells of Streptomyces sp. strain K-17 were disrupted by grinding with sea sand. D-glucose isomerase was partially purified with the fractionation by ammonium sulfate, Mn-treatment, DEAE-cellulose column chromatography, DEAE-sephadex (A-50) column chromatography and gel filtration of sephadex G-200. The enzyme was purified about 380 fold with 25 ％ recovery.

• Current Research on Agriculture and Life Sciences
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• v.14
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• pp.101-110
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• 1996

Using response surface methodology(RSM), the various conditions(agitation speed, air flow, glucose concentration) in jar fermentor culture were investigated to find the optimum conditions for maximum enzyme production. Central-composite-design was used to control the variable constant in the experiment. The glucose isomerase production of Steptomyces chibaensis J-59 was mostly affected by the air flow rate and glucose concentration. The estimated optimum conditions were as follows: 1% birchwood xylan, 1.5% CSL, 0.1% $MgSO_4{\cdot}7H_2O$, 0.012% $CoCl_2{\cdot}6H_2O$, pH 7.0; air flow, 2.2vvm; agitation speed, 587rpm; glucose concentration, 0.586%. Experimental values(7.43GIU/ml) for the enzyme production obtained from the given optimum conditions had a almost resemblane to response values(7.67GIU/ml) predicted by the RSM. The jar fermentor culture by the RSM produced xylose isomerase about 2.7 times as much as the baffled flask culture.

• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.385-392
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• 1996

Bacillus stearotheymophilus, a potent xylanolytic bacterium isolated from soil, was tested for the strain's strategies of pentose utilization and the evidence of substrate preferences. The strain metabolized glucose, xylose, ribose, maltose, cellobiose, sucrose, arabinose and xylitol. The efficacy of the sugars as a carbon and energy source in this strain was of the order named above. The organism, however, could not grow on glycerol as a sole growth substrate. During cultivation on a mixture of glucose and xylose or arabinose, the major hydrolytic products of xylan, B. stearothermophilus displayed classical diauxic growth in which glucose was utilized during the first phase. On the other hand, the pentose utilization was prevented immediately upon addition of glucose. Cellobiose was preferred over xylose or arabinose. In contrast, maltose and pentose were co-utilized, and also no preference on between xylose and arabinose. Enzymatic studies indicated that B. stearothermophilus possessed constitutive hexokinase, a key enzyme of the glucose metabolic system. While, the production of $^{D}$-xylose isomerase, $^{D}$-xylulokinase and $^{D}$-arabinose isomerase essential for pentose phosphate pathway were induced by xylose, xylan, and xylitol but repressed by glucose. Taken together, the results suggested that the sequential utilization of B. stearothermophilus would be mediated by catabolite regulatory mechanisms such as catabolite inhibition or inducer exclusion.

• Microbiology and Biotechnology Letters
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• v.17 no.4
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• pp.385-391
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• 1989

D-Glucose isomerase (D-xylose ketol isomerase, EC 5.3.1.5) was purified from the Alkalophilic Bacillus sp. No. 1911 by ammonium sulfate precipitation, DEAE-cellulose ion exchange chromatography followed by Sephadex G-150 gel filtration chromatography. Molecular weight of the purified enzyme was estimated to be 11, 000 by gel filtration on Sephadex G-200, and SDS-polyacrylamide gel electrophoresis showed that the enzyme consisted of four identical or similar subunits with a molecular weight of 43, 000. The enzyme was the most active at pH 7.5 and $65^{\circ}C$, and stable up to 7$0^{\circ}C$ at pH 7.5 and in the range of pH 6-9 at 6$0^{\circ}C$ by 30 min incubation in the presence of Co$^{++}$.

• The Korean Journal of Pharmacology
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• v.26 no.2
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• pp.121-126
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• 1990

The contractility of isolated rat atria, suspended in Krebs-Ringer bicarbonate medium containing 5.5mM glucose, was depressed approximately 50% by 0.1 mM of lidocaine. Partial recovery of the lidocaine-depressed contractility was achieved by the metabolizable substrates pyruvate, acetate, and fructose, but not by addition of glucose. Glucose produced the dose-dependent increase in the force of contraction of normal atria, whereas pyruvate, acetate, and fructose produced no significant effect in the contractile activity of the normal atria. In the absence of exogenous glucose lidocaine produced more marked depression of atrial contractility than that in the presence of exogenous glucose. The results of this study may confirm that the utilization of cardiac glycogen is also inhibited by lidocaine at sites of the glucose phosphate isomerase step or step between glycogen to glucose-6-phosphate.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1974.06a
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• pp.125.4-125
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• 1974

• Korean Journal of Food Science and Technology
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• v.10 no.4
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• pp.380-386
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• 1978

Enzymatic characteristics of glucose isomerase from Streptomyces spp. K-14 were studied. The optimum pH and temperature of the enzyme reaction are $pH\;7.5{\sim}8.0$ and $70^{\circ}{\sim}75^{\circ}C$, respectively, in the presence of 5 mM $MgSO_4{\cdot}7H_2O$ and 2 mM $CoCl_2{\cdot}6H_2O$. The enzyme activity was activated by both $Mg^{++}$ and $Co.^{++}\;Mg^{++}$ is required for the initial activation of the isomerization reaction, whereas $Co^{++}$ was essential for the increased stability of the enzyme protein. Glucose concentration up to 60% did not affect the reaction velocity as well as the equilibrium conversion of the enzyme.

• Korean journal of applied entomology
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• v.7
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• pp.61-64
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• 1969

By way of paper chromatography, free sugars in pycnial drops of Gymnosporangium haraeanum Sydow were investigated in regard of their biochemical interrelation with free sugars of Chinese juniper and pear leaf. The free sugar in pycnial drops of Gynnosporangium haraeanum Sydow were identified to only Fructose spot. Free sugars in Chinese juniper leaf were identified to Glucose. Galactose and two unknown spots. Free sugars of another sample in pear leaf were identified to spots of Glucose, Furctose and Galactose. The Arbutin from pear leaf was crystalized and its structure was identified to Glucose and Hydroquinone. The acetone powder of Emulsin was incubated for 1 hour at $40^{\circ}C$ with 0.05 M Arbutin substrate in test tube and purified by general method with the purpose of analysis of its. metabolic products. And the paper chromatographic analysis showed it to be Glucose spot. From the above results, this Fructose in pycinal drops of Gymnosporangium haraeanum Sydow is presumed to be the exchangeable from free sugars in pear leaf or to be the hydrolyzed of $\beta-glycoside$ (Arbutin)-the metabolic isomerization of Glucose into Fructose by pycnia isomerase.

• Journal of Microbiology and Biotechnology
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• v.18 no.5
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• pp.837-844
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• 2008

Glucose (xylose) isomerases from Streptomyces sp. have been used for the production of high fructose corn syrup for industrial purposes. An 11-kb DNA fragment containing the xyl gene cluster was isolated from Streptomyces lividans TK24 and its nucleotide sequences were analyzed. It was found that the xyl gene cluster contained a putative transcriptional repressor (xylR), xylulokinase (xylB), and xylose isomerase (xylA) genes. The transcriptional directions of the xylB and xylA genes were divergent, which is consistent to those found in other streptomycetes. A gene encoding XylR was located downstream of the xylB gene in the same direction, and its mutant strain produced xylose isomerase regardless of xylose in the media. The enzyme expression level in the mutant was 4.6 times higher than that in the parent strain under xylose-induced condition. Even in the absence of xylose, the mutant strain produce over 60% of enzyme compared with the xylose-induced condition. Gel mobility shift assay showed that XylR was able to bind to the putative xyl promoter, and its binding was inhibited by the addition of xylose in vitro. This result suggested that XylR acts as a repressor in the S. lividans xylose operon.

• Journal of Plant Biology
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• v.12 no.2
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• pp.15-22
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• 1969

By spectrophotometric assay method, the following enzymes could be detected in Dunaliella tertiolecta and Chlorella pyrenoidosa cell-free extracts: Hexokinase; Glucose-6-phosphate, 6-Phosphogluconate and Triosephosphate dehydrogenase; Transketolase; Phosphogluco and Ribosephosphate isomerase; Phosphoglucomutase; Phosphofructokinase; Fructosediphosphate aldorase and Ribulosephosphate 3-epimerase. Such enzymes are in accordance with the proposed pathway of glucose catabolism by D. tertiolecta as well as C. pyrenoidosa. Also, it could be estimated, under the presence of NADP, that pentose phosphate pathway were more active than glycolytic pathway in D. tertiolecta cell-free systems.