Bacillus licheniformis KFB-C14가 생산하는 내열성 Chitinase의 정체 및 특성

홍범식,윤호근,신동훈,조홍연 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 1996 한국미생물·생명공학회지 Vol.24 No.5

Bacillus licheniformis KFB-C14가 생산하는 내열성 chitinase를 30~70% ammonium sulfate fractionation, DEAE-Toyopearl 650M, Butyl-Toyopearl 650M, TSK-Gel Toyopearl HW-55F에 의해 정제도 66배, 수율 21%로 전기영동적으로 균일하게 정제하였다. 정제 단백질은 gel permeation chromatography에 의해 86,000±2,000의 분자량을 나타내었으며, SDS 전기영동에 의해 밝혀진 본 효소의 subunit 구조는 monomer였다. 효소 단백질의 안정성을 검토한 결과 80℃에서 30분 열처리에 의해 56%, 37℃에서 20분간 40% ethanol과 ethyl acetate, 단백질 변성제 등의 처리시에도 50% 이상의 잔존활성을 나타냄으로써 공업적으로 유용성이 높은 안정한 단백질로 판명되었다. 효소반응의 최적 pH와 온도는 pH 6.0과 60℃이었고 Mn^2+ 이온에 의해 효소 활성이 저해되었으나 EDTA, N-ethylmaleimide, p-chloromercuribenzoate 등에 의한 활성감소는 관찰되지 않음으로써 금속효소 또는 thiol계 효소에 속하지 않음을 알 수 있었다. 본 효소는 colloidal chitin, 시판용 chitin에는 반응성이 높았으나 exo형 chitinase의 대표적인 기질인 p-nitrophenyl-2-aectamido-2deoxy-β-glucopyranoside, NN'-diacetylchitobiose에는 전혀 반응성을 보이지 않는 전형적인 endo형의 chitinase였다. 본 효소는 colloidal chitin으로부터 주로 (GlcNAc)_2를, 반응시간 경과에 따라 (GlcNAc)_1과 (GlcNAc)_3을 생성하는 반응성을 보였다. Chitinase (EC 3.2.1.14) from culture fluid of Bacillus licheniformis KFB-C14 was purified 66-folds to homogenity in overall yield of 21% by ammonium sulfate fractionation, DEAE-Toyopearl, Butyl-Toyopearl and TSK-Gel HW-55F column chromatography. The enzyme protein had a molecular weight of about 86,000 and was composed of one subunit. The enzyme was significantly stable not only at high temperature but also on treatment with organic solvents and protein denaturants such as SDS, urea and guanidine·HCl. The optimum temperature and pH for reaction was 60℃ and 6.0,respectively. The enzyme activity was inhibited by only Mn^2+ ion, but not inhibited by EDTA, N-ethylmaleimide and pCMB. The enzyme had high activity with colloidal chitin (V_max: 421) and commercial chitin (V_max :480), but not with typical substrates of exo type chitinase. The thermostable chitinase had an useful reactivity for producing functional chitooligosaccharide, showing the production of (GlcNAc)_1, (GlcNAc)_3, and (GlcNAc)_2 as major product.

품종보호용 분자마커의 고추 내 도입

홍지영,최근원,김영채 경희대학교식량자원개발연구소 2006 硏究論文集 Vol.25 No.-

본 연구는 쥐의 adenosine deaminase(ADA) 유전자를 이용하여 개발된 고추 품종보호용 분자마커로서의 실용 가능성을 검토하기 위하여 실시되었다. 513bp 크기의 개발된 품종보호용 DNA 마커를 운반하는 A. tumefaciens LBA4404를 이용한 형질전환 실험에서 공동배양한 후 선발배지로 옮겨 배양한 '135Q' 와 '276F' 고추자엽 절편체는 두 계통 모두에서 84%와 80%의 높은 재분화율을 보였다. '135Q'와 '276F' 고추 자엽 절편체로부터 재분화된 신초들에 대한 분자마커 특히 primer를 이용한 PCR검정과 PCR로 확인된 잠정적인 형질전환 신초에 대한 Southern hybridization 분석 결과 품종보호용으로 개발된 513bp DNA 마커의 삽입을 확인하였다. PCR 검정 결과 '135Q'와 '276F' 고추 자엽 절편체로부터 재분화된 신초의 62.6%, 62.9%가 각각 형질전환체로 확인되었다. 이러한 안정적인 DNA 마커의 전이는 고추에서의 품종보호를 위한 활용 가능성을 제시한다. This study was carried out to investigate the possibility for the practical application of a molecular marker which was developed from mouse adenosine deaminase (ADA) gene for cultivar protection in hot pepper (Capsicum annuum L.). In the transformation of hot peppers using Agrobacterium tumefaciens LBA4404 carrying a 513 bp DNA marker for cultivar protection, the regeneration percentage from cotyledon explants of '135Q' and '276F' hot pepper lines after co-cultivation were 84 and 80%, respectively. Results of PCR analysis on regenerated shoots using marker-specific primers and Southern hybridization analysis on putative transgenic shoots confirmed by PCR indicated that the 513 bp DNA marker for cultivar protection was successfully transferred into the regenerated shoots. Twenty three and twenty four out of 33 and 37 regenerated shoots were transgenic in '135Q' and '276F' hot peppers, respectively. This stable transfer of the DNA marker suggested the possibility of practical application for cultivar protection in hot peppers.

내열성 Chitinase 생산균주의 분리 및 효소생산 특성

홍범식,윤호근,신동훈,조홍연 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 1996 한국미생물·생명공학회지 Vol.24 No.5

자연계 고온환경으로부터 내열성 chitinase 우수하고 반응산물로 N-acetyl-D-glucosamine 이량체(GlcNAc)_2를 생산하는 균주를 분리 선별하고 Bacillus licheniformis KFB-C14로 동정하였다. 선별균주의 효소생산 특성은 탄소원으로서 효소기질인 colloidal chitin이 첨가될 때만이 생합성이 유도되었으며 유도제의 첨가시기에 의해 효소생산이 크게 영향을 받았다. 각종 무기, 유기태 질소원 중 yeast extract가 활성과 비활성을 각각 약 2배 증가시켰으며 높은 친화도를 나타내었다. 균의 최대생육과 효소의 최대생산온도는 55℃이었다. 본 균주의 내열성 chitinase 생산에 미치는 최적배양조건은 1.2% colloidal chitin, 0.15% K_2HPO_4, 0.05% KH_2PO_4 0.01% MgSO_4·7H_2O, 0.1% yeast extract, pH 6.5의 배지를 55℃, 150rpm에서 40시간 회전진탕배양 하였을 때로 3.89 units/ml의 효소활성과 7.4 units/mg의 비활성을 나타내었다. A strain capable of producing thermostable chitinase suitable for chitooligosaccharide production was isolated from high temperature environment and identified as Bacillus licheniformis. The chitinase from Bacillus licheniformis KFB-C14 was only induced by addition of colloidal chitin into the basal medium as carbon source, showing the decrease of the chitinase production by supplemental addition of other carbon sources into the medium containing 1.0% colloidal chitin. Among organic and inorganic nitrogen sources, yeast extract was the most effective for the increase of total activity and specific activity, and had high affinity for the enzyme production. The optimum temperature of cell growth and thermostable chitinase production was 55℃. The optimum culture medium was composed of 1.2% colloidal chitin, 0.15% K_2HPO_4, 0.05% KH_2PO_4 0.01% MgSO_4·7H_2O, 0.1% yeast extract (pH 6.5). Bacillus licheniformis KFB-C14 produced the thermostable chitinase of 3.89 units per culture fluid and 7.4 units per mg protein under rotary shaking at 150 rpm for 40 hr.

광양지역의 지반전단강도 증가 특성

홍원표,송영석,이근하 중앙대학교 기술과학연구소 2000 기술과학연구소 논문집 Vol.30 No.-

본 연구에서는 연약지반개량공사가 실시된 광양지역을 대상으로 압밀기간동안 개량지반의 물리적, 역학적 변화특성 및 개량효과를 고찰되어 있다. 지반개량전 원지반에서 시료를 채취하고, 모래말뚝 타설직후, 압밀방치중(예상압밀도 50%) 및 압밀완료시(예상압밀도 90%)에도 시료를 채취하여 각각 토질정수를 조사 비교하였다. 그 결과 압밀이 진행되는 동안 지반의 강도는 증가하여, 일축압축강도로 구한 점성토지반의 강도증가율(C_u/P_o)이 0.36이 되었다. 그리고, 일축압축강도로 구한 점성토지반의 강도증가율(C_u/P_o)이 0.36이 되었다. 그리고, 일축압축강도와 함수비는 최대압밀응력에 대하여 유일함수관계를 보이고 있으며, 압밀완료시점(예상압밀도 90%)에서 추정된 비배수전단강도는 측정된 비례수전단강도와 비교적 잘 일치한다. In this study, both physical and mechanical properties of soft grounds are investigated during improvement works of soft grounds in Kwangyang. The properties of soil before ground improvement are compared with the properties of the improved ground after Sand Compaction Pile installation, during consolidation(degree of consolidation 50%), and at the end of consolidation(degree of consolidation 90%). From this result, improvement of the shearing strength of soft grounds can be deserved during consolidation, and the improving rate of shearing strength C_u/P_o is 0.36. The relationship between the shearing strength by unconfined compression tests, consolidation stress and water content shows that both the shearing strength and water content have an unique function relationship. The shearing strength predicted by Rutledge hypothesis shows relatives good agreement with the field strength.

랫드에서 법제유황과 비법제유황의 독성비교

김근수, 정유리, 이남진, 홍성희, 유종훈, 정재황, 강종구 충북대학교 동물의학연구소 2006 Journal of Biomedical and Translational Research Vol.7 No.2

본문참고

역간접촉산화법에 의한 연안 하구 수질개선에 관한 연구

김원근,이찬원,전홍표 경남대학교 환경문제연구소 2002 환경연구 Vol.25 No.-

A field study was conducted to investigate the removal efficiency and performance of contact oxidation treatment system installed and operated in two locations of stream flowing to the Masan Bay. The removal of organic matters from stream water flowing to the already eutrophicated bay is getting more important in order to restore the water quality. The removal efficiencies of BOD, SS and ABS loading rate were 52~63%, 50~70% and 60~85%, respectively, whereas 10~25% of total nitrogen and 25~40% of total phosphorus were only removed. The effluent water quality did not meet the goal class of water regulation standards. Inflow rates to contact oxidation treatment showed seasonal and hourly variations. The treatment capacity installed is now enough to handle the present inflows, thus it was suggested that this system should be operated to supply only the volume of oxygen to require the actual loading to the treatment system and the aeration system would be intermittently operated for the improvement of nitrogen and phosphorus removal. It was found that inflow rate should be controlled for detention time of contact oxidation to maintain at least more than 1.5 hr. When microbiological species of sludge and sludge accumulation in the lower steps of contact oxidation process was examined, proper draw-out of sludge from the system was also an important operating parameter.

사회주의권의 붕괴와 사회주의자의 대응

정홍근 진주교육대학교 1992 論文集 Vol.36 No.-

대학 핸드볼선수들의 개인적인 특성에 따른 스트레스 요인 분석

김홍백,은희관 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.4

The purpose of this study is to analyze the reasons for stress targeting 175 handball placers In the university (male 118, female 57) and to know the differences between stress reasons according to the players' characteristics. First, male players are stressful with senior's unfair behavior and leader's leadership, on the contrary women are under stress with leader's leadership, In gender, female players have much more stress than men especially in their skill, leader's leadership and referee's unfairness, Second, players show high stress with senior's unfair behavior and leader's leadership according to reasons for stress with career, grade, skill, and position. There Is no significant differences of reasons for characteristics.

공공양성훈련의 취업효과와 결정요인

장홍근 한국직업능력개발원 2003 직업능력개발연구 Vol.6 No.2

This study intends to analyze the employment effects of the middle and long-term training courses (over 6 months) supported by the national treasury and employment insurance funds, based on a survey data of 1,500 persons who have completed these training courses. In this study, employment effects were measured on two dimensions. One is the simple quantitative side of employment itself, and the other is the qualitative side of employment which implies wage level, employment status, the protection by social insurances, and the relationship between the contents of the training courses and those of actual works etc.. We analyzed the employment effects of public pre-employment training and the determinants of employment quality by the trainees' individual properties such as age, gender, marriage, household responsibility and training-related variables such as the degree of training substantiality, training courses, certificates got by training, training duration, employment guidance. Some important findings of our analysis are as follows. Of the individual properties, age and household responsibility are positively affect the employment. In terms of training properties, training substantiality, training duration, certificates got by training, employment guidance are positive determinants of employment qualities. This study gives us some implications regarding policy directions of public pre-employment training, including its target group, curriculum development and employment guidances etc..

한국 대학생의 경제 및 직업 가치관과 직업윤리

장홍근 가톨릭대학교 인간학연구소 2009 인간연구 Vol.0 No.16