• 한국잡초학회지
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• 제16권2호
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• pp.122-131
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• 1996

옥수수 잎으로부터 추출한 ALS를 대상으로 하여 CHL과 IMA의 상호작용, ALS의 기질인 pyruvate 및 2-ketobutyrate에 대한 친화도, 저해양식의 차이 등을 조사한 결과는 다음과 같다. 1. ALS 에 대한 CHL의 $I_{50}$값은 100nM이었으며 IMA의 값은 $5{\mu}M$로 나타나 CHL의 ALS 저해활성은 IMA보다 약 50배 정도 높았다. 2. ALS에 대한 시험관내에서의 실험에서 두 제초제의 동시처리시 상가적인 ALS의 저해효과가 나타났으나, 상호 순차적 체계처리의 경우에서는 먼저 처리한 제초제에 의한 저해효과가 지배적으로 나타났다. 3. 제초제에 의한 ALS 활성의 저해는 시험관내에서 10분 이내에 대부분 이루어졌다. 4. ALS의 활성은 분지아미노산에 의해 저해되었는데 Val과 Leu에 의한 저해가 Ile에 의한 저해보다 크게 나타났다. 또한 이들을 동시에 혼합처리하면 0.1mM의 농도에서도 ALS의 활성이 65% 정도 저하되었다. 5. 2-Ketobutyrate를 ALS의 기질로 첨가하면 pyruvate만을 기질로 사용하였을 때보다 측정가능한 ALS 활성이 2-ketobutyrate에 의해 농도의존적으로 감소되는 경향이었다. 6. ALS의 기질인 pyruvate에 대해 CH은 비경쟁적 저해제로 IMA는 반경쟁적 저해제로 작용하였다.

• 한국잡초학회지
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• 제16권2호
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• pp.132-139
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• 1996

제초제 cinosulfuron에 대해서 감수성이 각각 다른 두 품종을 선발해서 반응차이의 원인을 비교 검정하였다. 벼 어린식물체의 반응시험에서는 Indica type인 IR 74가 Japonica type인 화진벼보다 cinosulfuron에 대해서 높은 저항성을 보였다. 두 품종에서 추출한 ALS 효소의 활성은 cinosulfuron에 대해 비슥한 억제작용을 보였다. 10ppm cinosulfuron 처리에 대한 두 벼 품종간의 생육반응과 효소활성의 비교에서는 ALS효소 활성과 생육이 일치하는 경향을 보였다. IR 74의 효소활성과 생육은 시간이 지남에 따라 증가하는 경향이 있었으나, 화진벼에 있어서는 제초제 처리 후 5일째에 효소활성이 떨어졌으며 이시기에 유묘의 생육도 상당히 억제되었다. 두 벼 품종의 ALS효소는 cinosulfuron에 대해서 비슷한 감수성을 지닌 것으로 나타났으며 cinosulfuron을 처리한 유식물로부터 추출 가능한 효소의 양에서 차이가 나는 것으로 보아 다른 요인 즉 대사속도의 차이에 의해서 두 벼 품종의 생육반응이 다르게 나타난 것이 아닌가 사료된다.

• 한국미생물·생명공학회지
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• 제20권2호
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• pp.115-121
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• 1992

최소 배지에 여러가지 아미노산들을 첨가하여 배양한 Serratia marcescens ATCC 25419 세포 추출물에서 acetolactate syhthase(ALS)의 비활성도를 0.5mM에서 40 증가시킨 반면 8mM에서 60, 20mM에서 90 감소시켰다. Valine은 효소의 비활성도를 2-4 mM에서 20-40 정도 증가시켰고 20mM의 높은 농도에서 10 정도 감소시켰다.

• BMB Reports
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• 제30권1호
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• pp.13-17
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• 1997

The inhibitory effect of herbicides such as sulfonylurea derivatives, imidazolinones and pyrimidylsalicylate has been examined on the purified valine sensitive acetolactate synthase (ALS) from Serratia marcescens. The concentration of sulfometuron methyl which inhibits 50% of the ALS activity was 2.5 mM. The required concentrations of triasulfuron, primisulfuron methyl and imazaquin for the 50% inhibition of the ALS activity were 1 mM. The resistance of Serratia ALS to sulfometuron methyl, imazapyr and imazaquin is similar to that of E. coli ALS 1. However, pyrimidylsalicylate showed a potent inhibitory effect on the Serratia ALS almost 13 times more potent than on E. coli ALS II, which is known as herbicide-sensitive isozyme. The inhibitory mode was competitive against pyruvate. 150 value was determined to be $17{\mu}M$ in an assay mixture containing 20 mM pyruvate, and the $K_1$, value was calculated to be $0.4{\mu}m$ from the modified double reciprocal plot of 1/V versus $1/S^2$.

• Journal of Dental Anesthesia and Pain Medicine
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• 제17권3호
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• pp.235-240
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• 2017

Pulseless electrical activity (PEA) is a clinical condition characterized by unresponsiveness and lack of palpable pulse in the presence of organized cardiac electrical activity and is caused by a profound cardiovascular insult (e.g., severe prolonged hypoxia or acidosis, extreme hypovolemia, or flow-restricting pulmonary embolus). Amyotrophic lateral sclerosis (ALS) is a disease that is characterized by progressive degeneration of all levels of the motor nervous system. Damage to the respiratory system and weakness of the muscles may increase the likelihood of an emergency situation occurring in patients with ALS while under general anesthesia. We report a case of PEA during the induction of general anesthesia in a patient with ALS who presented for dental treatment and discuss the causes of PEA and necessary considerations for general anesthesia in patients with ALS.

• 근관절건강학회지
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• 제13권2호
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• pp.130-139
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• 2006

Purpose: This study was designed to present preliminary data for the development of appropriate nursing care system for the patients with ALS by analyzing their physical function. Method: The clinical data of 36 ALS patients, who visited ALS Clinic of H University Hospital in Seoul, were collected from January, 2006 to August, 2006. To determine the physical function, Norris ALS scale and Appel ALS Rating Scale were used. The data were analyzed by frequency, percentage, mean, standard deviation, range, t-test, ANOVA, using SPSS PC program. Results: The mean score of physical activity, muscle strength, upper extremity function, lower extremity function was 18.08, 27.72, 25.94, 25.19 respectively. There were significant differences in physical activity, muscle strength, and upper extremity function according to sender and comorbid disease(diabetes). Although sites of symptom onset were not statistically significant with all physical function, patients with bulbar onset showed relatively severe physical disabilities. Conclusion: The preliminary data on physical function of patients with ALS would be helpful for the development of ALS nursing guideline system.

• BMB Reports
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• 제32권4호
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• pp.393-398
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• 1999

Acetolactate synthase (ALS) catalyzes the first reaction common to the biosynthesis of L-valine, L-leucine, and L-isoleucine. ALS is the target site of several classes of herbicides, including the sulfonylureas, the imidazolinones, and the triazolopyrimidines. Two forms of ALS (ALS I and ALS II) which have different affinity for Heparin have been separated from etiolated pea seedlings. The substrate saturation curves of both ALS I and ALS II were hyperbolic in contrast to previous reports. The two forms of ALS showed significant differences in their physical and kinetic properties. The values of $K_m$ for ALS I and ALS II were 9.0 mM and 4.8 mM, respectively. The pI values for ALS I and ALS II were determined to be 5.3 and 5.75 by isoelectric focusing, respectively. The native molecular weights for ALS I and ALS II obtained by nondenaturing gel electrophoresis and activity staining were 124 and 244 kDa, respectively. They also exhibited different sensitivity to feedback inhibition by end-product amino acids and inhibition by Cadre, an imidazolinone herbicide.

• BMB Reports
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• 제30권4호
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• pp.274-279
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• 1997

Acetolactate synthase (ALS) catalyzes the first common step in the biosynthesis of branchedchain amino acids, valine, leucine, and isoleucine. ALS is the target site for several structually diverse classes of herbicides including sulfonylureas, imidazolinones. and triazolopyrimidines. We have purified ALS from etiolated barley shoots to homogeneity. The five major purification steps are ammonium sulfate fractionation, DEAE anion exchange, hydroxylapatite, Bio-Gel A gel filtration, and low pressure Mono-Q chrornatoqraphy. Approximately 170-fold purification was achieved and the yield was 0.45% of initial activity in the crude extract. Both SDS-PAGE and Western blot analysis showed a single polypeptide of ALS with an apparent molecular mass of 64 kDa. The result of nondenaturing gel electrophoresis with activity staining indicated that the molecular mass of its native form is approximately 225 to 250 kDa. The values of $K_m$ for pyruvate. pl. and optimum pH of ALS were determined to be 2.0 mM, 5.2. and 7.0. respectively Feedback inhibition studies showed that ALS is more susceptible to leucine than valine. And $IC_{50}$ value of Cadre, a class of irnidazolinones, is about $1.5\mu{M}$ for ALS.

• Bulletin of the Korean Chemical Society
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• 제24권12호
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• pp.1799-1804
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• 2003

Acetolatate synthase(ALS) catalyzes the first common step in the biosynthesis of valine, leucine, isoleucine in plants and microorganisms. ALS is the target of several classes of herbicides, including the sulfonylureas, the imidazolinones, and the triazolopyrimidines. To elucidate the roles of arginine residues in tobacco ALS, chemical modification and site-directed mutagenesis were performed. Recombinant tobacco ALS was expressed in E. coli and purified to homogeneity. The ALS was inactivated by arginine specific reagents, phenylglyoxal and 2,3-butanedione. The rate of inactivation was a function of the concentration of modifier. The inactivation by butanedione was enhanced by borate, and the inactivation was reversible on removal of excess butanedione and borate. The substrate pyruvate and competitive inhibitors fluoropyruvate and phenylpyruvate protected the enzyme against inactivation by both modifiers. The mutation of well-conserved Arg198 of the ALS by Gln abolished the enzymatic activity as well as the binding affinity for cofactor FAD. However, the mutation of R198K did not affect significantly the binding of FAD to the enzyme. Taken together, the results imply that Arg198 is essential for the catalytic activity of the ALS and involved in the binding of FAD, and that the positive charge of the Arg is crucial for the interaction with negatively charged FAD.

• BMB Reports
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• 제36권5호
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• pp.456-461
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• 2003

Acetolactate synthase (ALS) catalyzes the first common step in the biosynthesis of valine, leucine, and isoleucine. ALS is the target site for several classes of herbicides, including sulfonylureas, imidazolinones, and triazolopyrimidines. Two forms of ALS (designated ALS I and ALS II) were separated from barley shoots by heparin affinity column chromatography. The molecular masses of native ALS I and ALS II were determined to be 248 kDa and 238 kDa by nondenaturing gel electrophoresis and activity staining. Similar molecular masses of two forms of ALS were confirmed by a Western blot analysis. SDS-PAGE and Western blot analysis showed that the molecular masses of the ALS I and ALS II subunits were identical - 65 kDa. The two ALS forms exhibited different properties with respect to the values of $K_m$, pI and optimum pH, and sensitivity to inhibition by herbicides sulfonylurea and imidazolinone as well as to the feedback regulation by the end-product amino acids Val, Leu, and Ile. These results, therefore, suggest that the two ALS forms are not different polymeric forms of the same enzyme, but isozymes.