• Mycobiology
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• 제38권2호
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• pp.108-112
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• 2010

To investigate the possible roles of LAMMER kinase homologue, Lkh1, in Schizosaccharomyces pombe, whole proteins were extracted from wild type and lkh1-deletion mutant cells and subjected to polyacrylamide gel electrophoresis. Differentially expressed proteins were identified by tandem mass spectrometry (MS/MS) and were compared with a protein database. In whole-cell extracts, 10 proteins were up-regulated and 9 proteins were down-regulated in the mutant. In extracellular preparations, 6 proteins were up-regulated in the lkh1+ null mutant and 4 proteins successfully identified: glycolipid anchored surface precursor, $\beta$-glucosidase (Psu1), cell surface protein, glucan 1,3-$\beta$-glucosidase (Bgl2), and exo-1,3 $\beta$-glucanase (Exg1). These results suggest that Lkh1 is involved in regulating cell wall assembly.

• 한국미생물·생명공학회지
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• 제27권5호
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• pp.378-384
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• 1999

Protopectinase (PPases) are heterologous group of enzymes that degrade pectin from the insoluble protopection which is constituent of the middle lamella and primary cell wall of higher plants by restricted depolymerization. From the previous report[6], enzymatically separated plant cells, which are produced from plant tissues by PPases treatment, showed well-conserved cellular components with their rigid cell wall and this characteristic is applicable to preparation of novel food material. The purpose of this study is to investigate the effect of medium composition of PPase production from Bacillus subtilis EK11 which was selected as a PPase producer. Various carbon sources and concentrations on PPase production were studied and corn starch at 0.7% was the most effective for production of PPase. Among the nitrogen sources, yeast extract was the most effective for PPase production and the effect of (NH4)2SO4 was notable as inotganic nitrogen source. Inorganic compounds such as KH2PO4, K2HPO4, Na3-citrate.2H2O and MgSO4 were optimized for PPase production. PPase activity was inhibited by the adition of Ba2+ or Zn2+. The optimal medium for PPase production was devised: 0.7% corn starch, 0.3% yeast extract, 1.4% KH2PO4, 0.6% K2HPO4, 0.1% Na3-citrate.2H2O and 0.02% MgSO4. PPase production by using the optimum medium was carried out with shaking cultivation at 37$^{\circ}C$. The maximum PPase activity of 256unit/ml could be obtained after the cultivation for 48hrs. The activity was increased about 2.2timesthan the activity, 112 unit/ml, in basal medium.

• Archives of Pharmacal Research
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• 제17권1호
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• pp.26-30
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• 1994

Some ammonium oxalate soluble pectic fragments prepared from cultured cell wall of Ephycla distrahya elicited the accumulation of p-coumarocylamino acids (p-CAA) in E. distachya cultures while water soluble and alkali soluble fractions had no activity. Partial purification of the pectic fragments fraction using DEAE-cellulose chromatography afforded two active fractions (PS-I and PS-II) which were composed of mainly uronic acids (98-99 w/w %). They elicited the accumulation of p-CAA in an amount of 52-60 nmol per gram fresh weight of cultures. The acidic sugar compositions of PS-I and PS-II were found to be galacturonic acid and glucuronic acid by TLC analysis. They were supposed to act as endogenous elicitors of p-CAA accumulation. In order to investigate the effect of ethylene on p-CAA accumulation, Ethrel, which is known as ethylene generator, and ACC(1-aminocyclopropane-1-carboxylic acid), a direct precusor of ethylene biosynthesis, were added to the culture. However, they did not glycopeptide elicitor [(Con A-II)], either. Consequently, no relationships between ethylene and p-CAA accumulation were recognized. Several tentative elicitors were teted for their activity. Commercial yeast glucan, $CuCl_2$, laminarin and laminariheptaose had slight activity whereas ${\alpha}$-methylmannopyranoside and commercial yeast mannan had no elicitor activity. ${\alpha}$-methylmannopyranoside which has been known as a tentative inhibitor of glucan elicitor in Glycine max did not affect on the elicitor activity of Con A-II.

• Asian-Australasian Journal of Animal Sciences
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• 제13권8호
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• pp.1178-1187
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• 2000

Many immunostimulating substances have been developed to improve immunity of domestic animals, although their exact mode of action and effects are not clearly defined, and they are now widely used in feed industry. Bacterial lipopolysaccharides, called endotoxin, in particular may have a profound effect not only on the immune system but also on macrophages of the reticuloendothelial system. Glucans from a variety of yeast cell wall have been shown to stimulate both specific and non-specific immune responses and to increase growth performance in pigs. Recently, there has been great interest in the role of complex carbohydrates in disease prevention and treatment. Mannanoligosaccharide is a glucomannoprotein complex derived from the cell wall of yeast. Generally, it was also known that the deficiencies of some major vitamins (vitamin A, E and C) and minerals (chromium and selenium) lead to impaired immune system and, as a result, immune function is depressed and recovery delayed. On the other hand, many researchers suggested that one possible reason for the superior performance observed in pigs fed plasma protein may be because of the presence of biologically active plasma proteins (e.g., immunoglobulins) which are known to contribute to the health of the starter pig. And, immunoglobulins present in plasma protein have been implicated as contributing to the overall immunocompetence of the newborn pig. Other immunostimulants, lactoferrin and lysozyme, mainly found in milk and egg white, have been known as having bacteriocidal and bacteriolytic effect. When considering practical use of immunostimulants, the concept of using immunostimulants is new to many people and, in most cases, it is poorly understood how and why such compounds act, and how they should be used in practice. Therefore, in order to clarify the reason for discrepancies in results, special attention should be paid to the dose/response relationship of immunostimulants and the duration of the effect.

• The Plant Pathology Journal
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• 제28권3호
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• pp.227-238
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• 2012

Mitogen-activated protein kinase (MAPK) cascades are conserved signaling modules in the eukaryotic cells. They are involved in many major cell processes in fungi such as stress responses, vegetative growth, pathogenicity, secondary metabolism and cell wall integrity. In this review, we summarized the advances of research on the MAPK signaling pathways in Alternaria species. As major phytopathogenic fungi, Alternaria species reduce crop production. In contrast to the five MAPK pathways known in yeast, only three MAPK pathways as Fus3/Kss1-type, Hog1-type, and Slt2-type have been characterized in Alternaria. The Fus3/Kss1-type MAPK pathway participates in regulation of vegetative growth, conidiation, production of some cell-wall-degrading enzymes and pathogenicity. The Hog1-type pathway is involved in osmotic and oxidative stress, fungicides susceptibility and pathogenicity. The Slt2-type MAP kinases play an important role on maintaining cell wall integrity, pathogenicity and conidiation. Although recent advances on the MAPK pathways in Alternaria spp. reveal many important features on the pathogenicity, there are many unsolved problems regarding to the unknown MAP kinase cascade components and network among other major signal transduction. Considering the economic loss induced by Alternaria spp., more researches on the MAPK pathways will need to control the Alternaria diseases.

• 미생물학회지
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• 제40권1호
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• pp.54-59
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• 2004

아가리쿠스(Agaricus blazei)버섯의 균사체 배양조건을 최적화하여 유효성분인 $\beta$-glucan의 생성을 극대화시키고자 하였다. 아가리쿠스 균사체 배양시 탄소원과 질소원의 농도 및 종류별 배지를 검토한 결과 배지조성은 glucose 5% (w/v), yeast extract 0.5% (w/v), malt extract 0.5% (w/v), $KH_2PO_4$ 0.1% (w/v), $MgSO_4{\cdot}7H_2O$ 0.05% (w/v)가 최적이었다. 30L 발효조에서의 배양 조건은 pH 5.0, $28^{\circ}C$, 1 vvm, 300 rpm에서 균사체의 생육과 $\beta$-glucan의 생성이 가장 효과적이었다. 위 조건 중에서 세포 외 $\beta$-glucan의 생성을 증가시 키기 위해 초기 glucose의 첨가량을 4%로 낮추어 glucose에 의한 균사체 성장 저해작용을 최소화하는 한편, 배양 70시간 시점에 glucose 3%, yeast extract 0.1%, malt extract 0.1%의 추가 배지를 첨가하여 배양함으로써 batch 배양에 의한 2.8 g/L에 비해 2배 정도 증가한 5.2 g/L의 세포 외 $\beta$-glucan을 얻을 수 있었다. 또한 균사체 내의 세포벽 $\beta$-glucan을 효과적으로 추출하기 위해 세포벽분해효소인 lytic enzyme과 단백분해효소인 bromelain의 연속적인 효소반응으로 추출량이 3.5 g/L로 증가하여 균사체의 단순 열수추출에 비해 약 4배의 추출 수율이 향상되었다.

• Applied Biological Chemistry
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• 제29권4호
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• pp.359-365
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• 1986

대수증식(代數增殖) 중기(中期)의 S. cerevisiae에 $2{\times}10^{-3}M$의 paraquat를 처리(處理)하여 균체(菌體) 증식(增殖), 균체(菌體)의 일반적(一般的)형태 및 미세구조(微細構造)에 미치는 영향을 검토하였다. 균체(菌體)의 증식(增殖)은 Paraquat 처리(處理) 후(後) 조해(阻害)되기 시작하여 처리(處理) 6시간(時間) 이후(以後) 완전(完全)히 조해(阻害)되었다. 이 기간동안 탁도(濁度)는 0. 1에서 3.6으로, 건물(乾物) 중량(中量) 1ml당 2.75mg으로부터 3.35mg으로, 총균수(總菌數)는 ml당2 $1.14{\times}10^8cell$로부터 $2.15{\times}10^8cell$로 증가(增加)되었으나 6시간(時間) 이상(以上) 처리시간(處理時間)이 길어짐에 따라 역(逆)으로 감소되었고 사균율(死菌率)은 초기의 0.28%로부터 6시간(時間)째에는 5%, 12시간(時間)째에는 72%로 계속 증가(增加)되었다. Paraquat 처리(處理)에 의하여 균체(菌體)의 크기가 균일(均一)치 못하게 되었으며 세포벽(細胞壁)의 두께가 $0.15{\mu}m$(대조구(對照區) $0.20{\mu}m$)로 얇아지는 반면에 외측(外側)의 전자(電子)밀도가 높아졌으며 12시간(時間) 이상(以上)의 처리(處理)에 의하여 원형질막(原形質膜) 및 mitochondria와 같은 내막구조(內膜構造)가 와해되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제33권4호
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• pp.579-587
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• 2020

Objective: This study evaluated the effect of yeast products on growth performance, visceral organ weights, endogenous enzyme activities, ileal nutrient digestibility and meat yield of broiler chickens fed diets containing autolyzed whole yeast (WY) and yeast cell walls (YCW) at varying levels of inclusion. Methods: Nine dietary treatments consisting of WY or YCW included at 0.5, 1.0, 1.5, or 2.0 g/kg diet and a control diet without yeast supplementation was used in the experiment. Each of the nine treatments was replicated six times with nine birds per replicate. Birds were housed in cages, in climate-controlled rooms and fed starter, grower and finisher diets. Results: There was an improvement (p<0.05) in body weight gain and feed conversion ratio on d 10, 24, and 35 for birds fed 1.0 to 2.0 g/kg WY or YCW diet. Small intestine weight was heavier on d 10 and 24 for birds on higher levels of WY and YCW compared to the control group. On d 10 and 24, there was a significant increase (p<0.05) in tissue protein content and pancreatic enzyme activities (trypsin and chymotrypsin) of birds on 1.5 to 2.0 g/kg WY and YCW diets compared to the control group. Compared to the control group, birds on WY (2.0 g/kg diet) and YCW (at 1.5 and 2.0 g/kg diet) had better (p<0.05) protein digestibility on d 24. On d 35, there was significant improvement (p<0.05) in percentage of carcass, absolute and relative breast weight for broiler chickens fed WY and YCW mostly at 2 g/kg diet compared to birds on the control diet. Conclusion: Supplementation of diets with autolyzed WY and YCW products especially at 1.5 to 2.0 g/kg diet improved broiler chicken performance and meat yield through their positive effects on ileal protein digestibility and pancreatic enzyme activities.

• 한국식품과학회지
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• 제34권5호
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• pp.867-872
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• 2002

정미성이 높은 효모 추출물을 얻고자 각종 효소의 사용에 대한 최적 조합 및 공정법을 알아보기 위하여 맥주 폐효모박을 각종 효소로 처리하여 효모추출물 중의 정미성분(IMP, GMP 및 유리아미노산)을 측정하여 비교, 분석하였다. Glucanase(0.5%) 처리에 의한 효모추출물중의 조단백질 함량은 33.6% 이었다. Tunicase(1%) 28.0% 와 무처리구 21.1%에 비해 최고 1.6배의 증가를 보였다. 단백질 분해효소처리에 의한 조단백질의 함량은 bromelin(1%), protamex(1%) 처리에서 각각 30.8%, 29.8%로 무처리구에 비해 최고 1.4배의 증가를 보였다. 효소 복합처리에 의한 상승효과는 glucanase(0.5%)+protamex(1%) 처리구에서 조단백질의 함량이 34.4%로 나타나 glucanase 단독처리구의 33.6%보다 높은 함량을 나타냈다. IMP+GMP 총함량은 glucanase + phophodiesterase + adenyldeaminase (G+P+A) 혼합 처리구에서 1,066 mg/100 g, glucanase + ptotamex + phophodiesterase + adenyldeaminase (G+Pro+P+A) 혼합 처리구에서는 1,047 mg/100 g으로 비슷하였다. 유리아미노산의 함량은 protamex가 첨가된 G+Pro+P+A 혼합처리구에서 2,302 mg/100 g으로 가장 높게 나타났다. 따라서 IMP, GMP 및 유리아미노산의 함량을 모두 고려해 볼 때 세포벽 분해효소 (gulcanase 0.5%, 12시간), 단백질 분해효소 (protamex 1%, 3시간), 핵산 분해효소 (phosphodiesterase 0.1%, 3시간) 및 핵산 전이효소 (adenyldeaminase 1%, 1.5시간)를 순차적으로 적용시켜 가수분해시키는 것이 효모 추출물의 정미성을 높이는 최적의 효소 복합 사용공정으로 판단되었다.

• Journal of Microbiology and Biotechnology
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• 제28권6호
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• pp.917-930
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• 2018

Intracellular synthesis of silver/silver chloride nanoparticles (Ag/AgCl-NPs) using Meyerozyma guilliermondii KX008616 is reported under aerobic and anaerobic conditions for the first time. The biogenic synthesis of Ag-NP types has been proposed as an easy and cost-effective alternative for various biomedical applications. The interaction of nanoparticles with ethanol production was mentioned. The purified biogenic Ag/AgCl-nanoparticles were characterized by different spectroscopic and microscopic approaches. The purified nanoparticles exhibited a surface plasmon resonance band at 419 and 415 nm, confirming the formation of Ag/AgCl-NPs under aerobic and anaerobic conditions, respectively. The planes of the cubic crystalline phase of the Ag/AgCl-NPs were confirmed by X-ray diffraction. Fourier-transform infrared spectra showed the interactions between the yeast cell constituents and silver ions to form the biogenic Ag/AgCl-NPs. The intracellular Ag/AgCl-NPs synthesized under aerobic condition were homogenous and spherical in shape, with an approximate particle size of 2.5-30nm as denoted by the transmission electron microscopy (TEM). The reaction mixture was optimized by varying reaction parameters, including temperature and pH. Analysis of ultrathin sections of yeast cells by TEM indicated that the biogenic nanoparticles were formed as clusters, known as nanoaggregates, in the cytoplasm or in the inner and outer regions of the cell wall. The study recommends using the biomass of yeast that is used in industrial or fermentation purposes to produce Ag/AgCl-NPs as associated by-products to maximize benefit and to reduce the production cost.