• 제목/요약/키워드: initial culture condition

검색결과 186건 처리시간 0.027초

Initial Characterization of yliH in Salmonella typhimurium

  • Park, Kyung-Hwa;Song, Mi-Ryung;Choy, Hyon-E.
    • Journal of Microbiology
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    • 제45권6호
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    • pp.558-565
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    • 2007
  • Using microarray analysis, we determined those Salmonella genes induced at the entry of stationary phase, and subsequently discovered that uncharacterized yliH was induced most dramatically. We set out to establish the molecular mechanism underlying the stationary phase induction of yliH under the standard culture condition, LB with vigorous aeration, by analyzing its promoter activity in various mutant backgrounds, lacking stationary phase ${\sigma}$, $RpoS^-$, or stringent signal molecules ppGpp, ${\Delta}relA$ ${\Delta}spoT$. It was found that the stationary phase induction of yliHp was partially dependent on rpoS but entirely dependent on ppGpp. DNA sequence analysis revealed that the Salmonella yliH gene is composed of 381 base-pair nucleotides, with overall amino acid sequence revealing 76.38% amino acid identity and 88.98% similarity with Escherichia coli yliH, although no motif from data base was noted for its possible role. Recently however, it has been reported that yliH in E. coli was implicated in biofilm formation and motility by repressing these activities (Domka et al., 2006). We have constructed a mutant Salmonella deleting yliH gene by allele replacement and examined its phenotype, and found that the yliH in Salmonella more or less affects motility and adherence by enhancing these activities. The effect on biofilm formation in Salmonella was uncertain. Moreover, addition of cloned yliH of E. coli into Salmonella did not reduce motility or adherence. Taken together, it appears that the pathways implicating yliH for biofilm formation and motility in E. coli and in Salmonella are somewhat different.

치성감염으로 인한 패혈증: 증례보고 (Sepsis Developed from an Odontogenic Infection: Case Report)

  • 김문섭;김수관;문성용;오지수;박진주;정미애;양석진;정종원;김정선
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제33권5호
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    • pp.445-448
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    • 2011
  • Mortality associated with maxillofacial infection is relatively low due to the development of antibiotics, and improved oral care. However, inappropriate treatment, delayed treatment, old age, underlying systemic disease, and drug-resistant microorganisms can potentially result in life threatening situations such as cavernous sinus thrombosis, mediastinitis, and sepsis. Sepsis is the most dangerous state with high mortality, ranging from 20~60%. The treatment of sepsis involves properly monitoring vital functions, fluid resuscitation, surgical drainage, and empirical use of high doses of antibiotics until culture results are available. Ventilatory support maybe be required as well. We encountered a 64-year-old patient who died from sepsis that developed as the result of an odontogenic infection. The initial diagnosis was right temporal, infraorbital, buccal, pterygomandibular space abscess. Despite surgical and medical supportive care, the condition progressed to sepsis and after four days the patient died due to multiple organ failure.

Pseudomonas sp.에 의한 Nonylphenol Ethoxylates의 Kinetics (Biodegradation Kinetics of Nonylphenol Ethoxylates by Pseudomonas sp.)

  • 김수정;이종근;이상준
    • 한국환경과학회지
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    • 제2권4호
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    • pp.271-278
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    • 1993
  • Nonylphenol ethoxylates-30을 분해할 수 있는 Pseudomonas sp.를 분리, 동정하였다. Nonylphenol ethoxylates-30 의 최적분해조건은 탄소원으로 nonylphenol ethoxylates-30 1.0 g/ι, 질소원으로 ammonium nitrate 0.02 g/ι, pH 7.5, 30였다. 최적분해 조건에서 nonylphenol ethoxylates-30은 배양 30시간 후 89%가 분해되었다. 최적분해조건에서 nonylphenol ethoxylates-30의 초기농도가 각각 100 ppm, 500 ppm, 1000 ppm, 5000 ppm일 때 시간에 따른 분해율을 수식으로 설명할 수 있는 가장 적합한 분해 kinetics는 각각 first order model, Monod no growth model, Monod with growth model로 나타났다.

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Vibrio vulnificus CYK 279H에서 Collagenolytic Protease 생산을 위한 최적배양조건 (The Optimal Culture Condition for the Collagenolytic Protease Production from Vibrio vulnificus CYK279H)

  • 강성일;김영문;장영부;임동중;공재열
    • KSBB Journal
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    • 제19권4호
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    • pp.295-300
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    • 2004
  • 해양유래미생물에서 gelatin 분해능이 우수한 균주 Vibrio vulnificus CYK 279H를 이용하여 최적 효소활성조건을 검토하였다. 온도와 초기 pH는 $25^{\circ}C$, 7.5에서 높은 것으로 나타났으며, 단당, 이당, 다당류를 첨가하여 탄소원의 영향에서는, 0.3% (w/v) galactose 에서, 유$.$무기 질소원으로는 0.6% (w/v) yeast extract와 4.0% (w/v) gelatin, 0.2% (w/v) (NH$_4$)$_2$SO$_4$에서 효소활성이 가장 높게 나타났다. 염 농도로는 2.0% (w/v) NaCl, 금속이온은 Fe$^{2+}$를 첨가하였을 때 효소활성이 증가되었다. 선정된 최적배양조건에서 Vibrio vulnificus CYK 279H를 배양한 결과, 18 h 배양시 73 Unit/1로 기본배지 20 Unit/1보다 활성이 3.7배 증가한 것으로 확인되었다.

가자미 식해로부터 콜레스테를 분해세균의 분리 및 특성 (Isolation and Characterization of Cholesterol Degradation Bacteria from Korea Traditional Salt Fermented Flat Fish)

  • 김관필;이창호;박희동
    • 한국식품저장유통학회지
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    • 제8권1호
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    • pp.92-101
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    • 2001
  • 전통 발효 식품인 가자미 식 해로부터 cholesterol oxidase 생산성이 있는 균주를 분리하고 이들 분리된 균주들로 부터 여러 단계의 균주 선별시험을 통하여 cholesterol oxidate 생산성이 우수한 미생물을 선별하여 그 특성을 조사하였다. Cholesterol oxidase의 생산성이 가장 우수한 SFF34의 배양학적, 생리학적 특성 및 세포벽 지방산 조성을 조사하여 Bergey's Mannual of Systematic Bacteriology의 분류기준에 따라 동정한 결과 Bacillus sp. 또는 그 유연균으로 동정되어 분리균을 Bacillus sp. SFF34로 명명하였다. Cholesterol oxidase의 생산 조건을 검토한 결과 최적 배지 조성은 2.0% glucose, 0.5% yeast extract, 0.03% MgSO$_4$.7$H_2O$, 0.02% $K_2$HPO$_4$, 0.2% NH$_4$NO$_3$, 0.2% Cholesterol로 판명되었으며, 배양 조건은 3$0^{\circ}C$, 초기 pH 7.0, 진탕속도는 150rpm에서 24시간 배양시효소 생성이 가장 우수하였다 (2.42 U/ml).

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Cancer Patients Are at High Risk of Mortality if Presenting with Sepsis at an Emergency Department

  • Prachanukool, Thidathit;Tangkulpanich, Panvilai;Paosaree, Possawee;Sawanyawisuth, Kittisak;Sitthichanbuncha, Yuwares
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권7호
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    • pp.3423-3426
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    • 2016
  • Background: Sepsis is an emergency condition with high mortality and morbidity rate. There are limited data on the association of cancer as a risk factor for mortality in sepsis patients in the emergency department (ED). Materials and Methods: This retrospective study was conducted at the ED, Faculty of Medicine, Ramathibodi Hospital, Bangkok, Thailand. The study period was between January 1st and December $31^{st}$, 2014. The inclusion criteria were as follows: adult patients over 15 years of age who presented at the ED with suspicion of sepsis, received treatment at the ED, and whose blood culture was found to be positive. Clinical data were recorded from medical records including the Mortality in Emergency Department Sepsis score (MEDS score). The primary outcome of this study was mortality at one month. Multivariate logistic regression analysis was used to identify independent factors associated with death. Results: During the study period, there were 775 eligible patients. The two most common pathogens identified from blood cultures were Staphylococcus aureus (193 patients; 24.9%) and Escherichia coli (158 patients; 20.4%). At one month after presenting at the ED, 110 patients (14.2%) had died. There were four significant factors for death, having cancer, being on an endotracheal tube, initial diagnosis of bacteremia, and high MED scores. Having cancer had an adjusted OR of 2.12 (95% CI of 1.29, 3.47). Conclusions: Cancer patients have double the risk of mortality if presenting with sepsis at the ED.

Morphological Diversity of Mortierella alpina: Effect of Consumed Carbon to Nitrogen Ratio in Flask Culture

  • Park, Enoch Y.;Yasuhisa Koike;Cai, Hong-Jie;Kenichi Higashiyama;Shigeaki Fujikawa
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제6권3호
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    • pp.161-166
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    • 2001
  • The influence of the consumed carbon to nitrogen (C/N) ratio on mycelial morphology was investigated in cultures of Mortierella alpina using shake flasks. The consumed C/N ratio was varied from 5 to 32 under the condition that the total initial amount of the carbon and nitrogen sources was 50g/L. The whole mycelia and filamentous mycelia exhibited no relationship with the consumed C/N ratio below a consumed C/N ratio of 20 in the presence of either excess carbon or excess nitrogen. However, when the consumed C/N ratio increased higher than 20, the mycelial sizes increased in proportion to the consumed C/N ratio. However, the area ratio of filamentous mycelia to total mycelia was found to be independent of the consumed C/N ratio, and remained constant at 0.82. In the case of a fixed consumed C/N ratio of 20, the whole mycelia and filamentous mycelia increased in proportion to the degree of the medium strength, yet the area ratio of filamentous mycelia to total mycelia remained unchanged at 0.76. Accordingly, these results show that fungal morphology and mycelial size are both affected by the ratio of carbon to nitrogen. The findings of the current study will be helpful in obtaining the efficient production of useful bioproducts from fungal cultures.

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Effects of Soil Moisture Stress at Different Growth Stage on Growth, Yield and Quality in Rice

  • Park, Hong-Kyu;Choi, Weon-Young;Kang, Si-Yong;Kim, Young-Doo;Choi, Won-Yul
    • 한국작물학회지
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    • 제44권2호
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    • pp.143-148
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    • 1999
  • Soil moisture condition is an important limiting factor in growth and yield in rice culture. The purpose of this study was to compare the influence on the growth, yield and Quality of rice subjected to soil moisture stress (SMS) at different growth stages. Ajaponica rice cultivar, Dongjinbyeo, was cultured under flooded conditions in a plastic container filled with silty loam soil. The container was subjected to SMS until the initial wilting point (IWP) coincided with about 10% in soil moisture content and about-200 kPa in soil matric potential, and was then irrigated again, at 6 and 5 of main growth stage in 1996 and 1997, respectively. At maturity, the plant height, tiller number, leaf area and top dry weight were decreased more in SMS treatments at the early stage than the late stage. The averaged yield index of SMS to control in both years was lowest at meiosis (62.5%), which primarily resulted from lower percent ripened grain and 1,000 grain weight, and second' reduced the spikelet number per panicle and panicle number per hill, and followed at tillering stage (68.5%) which resulted from the lower production in tiller number and top dry matter during and after SMS treatment. The percent-age of read rice in SMS plants varied with the treatment stage as order of lower at meiosis (44.0%), heading (53.9%), panicle initiation (70.1%), tillering (72.1%), ripening (75.8%) and 5 days after transplanting (DAT) (79.0%). Protein content in brown rice was slightly larger in SMS at late growth stage than the control, while the contents of fat and ash differed very little between SMS and control. Contents of Mg and K and Mg/K in brown rice with SMS were lower at some treatment stages such as at ripening or panicle initiation.

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온라인 게임 기업의 제품 다원화를 위한 제휴 전략 진화에 관한 연구 (The Study on Evolutionary Process of Online-Game Companies' Alliance Strategy for Product Diversification)

  • 장용호;정원조
    • 한국게임학회 논문지
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    • 제11권2호
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    • pp.57-68
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    • 2011
  • 본 연구는 새롭게 탄생한 온라인 게임 기업이 시장 성장주기(도입기-성장기-성숙기)에 따라 어떻게 다원화 전략을 행하여 왔는가를 자원기반이론과 진화이론의 관점에서 실증적 사례 분석을 통해 그 역사적 진행 과정을 체계적으로 분석하였다. 초기 온라인 게임 기업들은 진입 조건(장르, 기술력, 이용자특성)에 따라 다른 전략(기술역량기반, 서비스역량기반)을 통해 성장하였다. 이후 성장기에 이들 기업들은 제품 다원화를 위해 자원기반(기술기반전략, 서비스기반전략)에 따라 경로의존적 제휴 전략(보완적, 대체적 제휴)을 수행하여왔다. 그러나 성숙기에 이들 기업들은 기존 경로의존적 전략을 뛰어넘어 이용가능한 모든 자원 역량을 동원하는 통합 전략을 자연적으로 선택함으로서 시장 성장주기에 탄력적으로 적응하였다. 이러한 분석 결과는 진화이론과 자원기반이론을 복합적으로 적용하여 새롭게 탄생한 산업에서 시장의 단계별 성장주기에 따라 온라인 게임 기업의 제휴 전략 패턴이 어떻게 자기조직화 하고 있는지 분석함으로써 새로운 산업적, 정책적, 이론적 모델이 요구되고 있음을 제시하고 있다.

한국 전통발효식품인 청국장에서 분리한 Bacillus methylotrophicus에 의한 항산화물질의 생산 (Antioxidant Production by Bacillus methylotrophicus Isolated from Chungkookjang, Korean Traditional Fermented Food)

  • 이나리;우가영;장준혁;이상미;고태훈;이희섭;황대연;손홍주
    • 한국환경과학회지
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    • 제22권7호
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    • pp.855-862
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    • 2013
  • Although antioxidant activities of Korean traditional fermented foods were reported by many researchers, study on antioxidant activity of microorganism originated from Korean traditional fermented foods was little. Therefore, we improved condition for antioxidant production by a bacterium isolated from home-made Chungkookjang. We selected a bacterial strain, which showed the highest antioxidative activity, from Chungkookjang and then named GJ. The selected GJ strain was identified as Bacillus methylotrophicus by alignment data of 16S rRNA gene nucleotide sequences. Improved medium compositions for DPPH radical scavenging activity were 0.25% sucrose, 1% peptone, 0.01% $MgSO_4{\cdot}7H_2O$ and initial pH 6.5, respectively. Optimal culture conditions were $30^{\circ}C$, 200 rpm and 4% inoculum volume, respectively. In improved conditions, DPPH radical scavenging activity of GJ reached to 91% in a short time. The strain GJ also possessed ACE inhibition and other antioxidative activities; ACE inhibition activity (49.4%), ABTS radical scavenging activity (99.8%), metal chelating activity (67.9%), SOD-like activity (36.5%) and reducing power ($A_{700}$ = 5.982) were observed, respectively. Therefore, our results suggest that B. methylotrophicus GJ strain may be potential candidate for functional foods, cosmetic products for anti-aging and medicine for diseases caused by oxidative stress.