• Journal of Nutrition and Health
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• 제1권2호
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• pp.107-115
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• 1968

Number of aspects, not only nutritional but social as well as political involved in human starvation pose nowadays global problems. In order to help establish the minimum nutritional requirements in the daily life of a man and to free people as well from either undernourishment, malnutrition or even starvation many workers have devoted themselves so far on the research programs to know what and how number of metabolic events take place in animals in vivo. It is the purpose of the present paper to examine in effect to what extent both of the protein and nucleic acids (DNA & RNA) together with an enzyme, guanine deaminase, which converts guanine into xanthine and in turn ends up to uric acid as an end product, undergo changes, quantitatively during acute starvation, using the mouse as an experimental animal. The mouse was strictly inhibited from taking foods except drinking water ad libitum and was sacriflced 24, 48, and 72 hours following starvation thus acutely induced. The animals consisted of two experimental groups, one control and another starvation groups, each being consisted of 6-24 mice of whose body weights ranged in the vicinity of 10 g. The animals were sacriflced by a blow on the head, followed by immediate excision of their livers into ice-cold distilled water, washing adherent blood and other contaminant tissues. The liver was minced foramin, by an all-glass homogenizer immersing it in an ice-bath, followed by subsequent fractionatin of the homogenate (10% W/V in 0.25M sucrose solution made up with 0.05M phosphate buffer of pH 7.4). For the liver protein and guanine deaminase assay, the 10% homogenate was centrifuged at 600 x g for 10 minutes to eliminate the nuclear fraction; and for the estimation of DNA and RNA, the homogenate was prepared by the addition of 10% trichloroacetic acid in order to free the homogenate from the acid-soluble fraction, the remaining residue being delipidate by the addition of alcohol and dried in vacuo for later KOH (IN) hydrolysis. The changes in body and liver wegihts during acute starvation were checked gravimetrically. Protein contents in the liver were monitored by the method of Lowry et al; and guanine deaminase activities were followed by the assay of liberated ammonia from the substrate utilizing the Caraway's colorimetry. The extraction of both DNA and RNA was performed by the Schmidt-Thannhauser's method, which was followed by Marmur's method of purification for DNA and by Chargaff's method of purification for RNA. The determinations of both DNA and RNA were carried out by the diphenylamine reaction for the former and by the orcinol reaction for the latter. The following resume was the results of the present work. 1. It was observed that the body as well as liver weights fall abruptly during starvation, and that the loss of body weight showed no statistical correlation with the decreases in the content of liver protein. 2. The content of liver protein and activity of liver guanine deaminase activity as well decline dramatically, and the specific activities of the enzyme (activity/protein), however, decreased gradually as starvation proceeded. 3. Both of the nucleic acids, DNA and RNA, showed decrements in the liver of mouse during acute starvation; the latter, however, being more striking in the decline as compared to the former. 4. The decreases in the liver protein content as resulted from the acute starvation had no statistically significant correlation with the decrements of DNA in the same tissue, but had regressed with a significant statistical correlation with the fall of RNA in the tissue. 5. The decrease in the activity of guanine deaminase in the liver of mouse during acute starvation was functionally more proportional to the decrease in RNA than DNA, and moreover correlated with the changes in the content of the liver protein. 6. The possible mechanisms involved during in this acute starvation as bring the decreases in the contents of DNA, protein, and guanine deaminase were discussed briefly.

• 약학회지
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• 제26권3호
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• pp.175-180
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• 1982

The intermediate of N'-nitrosonornicotine may bind to the guanine moiety of a G-C base pair. The hydrogen bond of the base pair may be broken and a new hydrogen bond can form between the intermediate and the guanine. It results in the "short" type of DNA repair.NA repair.

• 한국식품영양학회지
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• 제1권2호
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• pp.37-42
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• 1988

In attempts to obtain IMP Producting strains, Brevibacterium ammoniagenes ATCC 6872 was treated wilts N.1.6. Adenine-guanine requiring mutants were obtained from Brevibacterium ammoniagenes ATCC 6872, and then a strain of them was selected for production of IMP and named Brevibacterium ammoniagenes No.9(ade', gu'). The production of IMP by Brevibacterium ammoniagenes nuts No.9 was about 3mg/ml for 4 day of culture. The optimal concentration of adenine and guanine was 150mg/mg.

• Bulletin of the Korean Chemical Society
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• 제29권3호
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• pp.539-540
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• 2008

• Bulletin of the Korean Chemical Society
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• 제33권12호
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• pp.4255-4257
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• 2012

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.184.3-185
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• 2003

Inosine 5'-monophosphate dehydrogenase (IMPDH) is a critical enzyme in the regulation of cell proliferation and differentiation. This enzyme catalyzes the $NAD^+$-dependent oxidation of IMP to XMP, the rate limiting step in de novo biosynthesis of guanine nucleotides. Therefore, the biochemical effect of IMPDH inhibition in sensitive cell types is decrease in intracellular guanine nucleotide levels, and the decrease in cellular GTP and deoxy GTP pool levels blocks DNA and RNA synthesis in rapidly proliferating tumor cells. (omitted)

• 한국미생물·생명공학회지
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• 제9권1호
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• pp.45-50
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• 1981

Adenine-guanine 동시영양요구성인 Brevibacterium ammoniagenes D-21530을 사용하여 5'-IMP을 생산할 경우, 5'-IMP생성에는 탄소원으로 fructose가 glucose보다 효율적이었다. 반면에 균 생육에는 glucose를 탄소원으로 사용하는 것이 좋았다. Glucose와 fructose를 혼합하여 사용할 때 균 생육을 적절히 조절하여 5'-IMP축적을 증가시켜 줄 수 있었으며 fructose와 glucose의 혼합당에 있는 fructose의 함유율을 20∼40%범위로 하였을 때 5'-IMP생성이 최대가 되었고 fructose 단독으로 사용할 때보다 약 40% 증가되었다. 또한 영양요구성물질인 adenine과 guanine의 첨가농도가 증가함에 따라 균생육이 촉진되나 150㎎/l 이상에서는 정상상태였고, 5'-IMP생성은 50㎎/l 까지는 첨가 농도에 따라 급격히 증가하나 그 이상에서는 감소하였다.

• 대한화학회지
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• 제54권4호
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• pp.429-436
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• 2010

Guanine (1)으로부터 생물활성이 있는 halogenopurines계 화합물을 합성하였다. Guanine을 acetic anhydride와 반응시켜서 2,9-diacetylguanine (2-1)을 합성하여 얻어진 화합물을 $POCl_3$와 반응시켜서 화합물 3a를 합성하고, 다음 단계에서 2-amino-6-halogenopurines (3b-d)를 합성하였다. 2-Halogenopurines (2-2a-d, 4-2a-d, 5a-d)을 2-amino-6-substituted purines (1, 3a, 4-1)로부터 효율적으로 합성한 후에, 새로운 화합물인 2-2a, 2-2c, 2-2d, 4-2c, 4-2d, 5b, 5c 및 5d를 합성하였다. 합성한 화합물의 구조를 원소분석, $^1H$ NMR, mass spectral data로 확인하였으며, 합성한 화합물에 대한 항균 활성을 시험하였다.

• Archives of Pharmacal Research
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• 제20권6호
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• pp.550-554
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• 1997

Chlorambucil is known to alkylate primarily N7 of guanine and N3 of adenine to induce DNA monofunctional adducts and interstrand cross-links (ISC). We have investigated the sequence specificity for DNA ISC induced by chlorambucil using duplex oligomers containing a defined cross-linkable sequences $ 5^{I}-A*TT, 5^{I}-G*TTor5^{I}-G*CC$ under bar which asterisk indicates the potential cross-linking site and underlined base indicates the potential cross-linking site on the opposite strand. An analysis of 20% denaturing polyacrylamide gel electrophoresis showed that chlorambucil was albe to induce DNA ISC in the duplex oligomers containing a sequence $5^I-GCC$. The formation of DNA ISC was not observed in the duplex oligomers containing sequences $5^I-ATT$. or $5^I-GTT$. These results indicate that chlorambucil induces guanine-guanine DNA ISC but not guanine-adenine or adenine-adenine DNA ISC. In addition, we have tested the ability of chlorambucil to induce DNA ISC within $5^I-GNNC$ or $5^I-GNNC$sequences using duplex oligomers containing the sequence$5^I-G^4G^3G^2^C$. The result of DNA strand cleavage assay showed that DNA ISC was formed at the $5^I-GGC$ sequence (an 1,3 cross-link, $G^1-G^3$) but not at $5^I-GGGC$ (an 1,4 cross-link, $G^1-G^4$) or $5^I-GC$ sequence (an 1,2 cross-link, $G^1-G^2$).

• 대한화학회지
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• 제40권4호
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• pp.229-234
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• 1996

Benzo[a]pyrene(BP)과 그들의 대사체들의 발암성을 PM3의 방법으로 조사하였다. BP분자내의 transbutadiene(TB)frame을 형성하는 4, 5, 5a, 그리고 6번 위치가 발암활성영역임을 LUMO 전자밀도로 예측하고 Ultimate carcinogen인 BP-triol의 발암활성영역이 10, 10a, 12c, 그리고12b 위치로 변화함을 알았다. TB 영역에 해당하는 Guanine의 HOMO와 BP-triol의 LUMO 사이의 전하이동량이 가장 큼을 알았다.