• Title/Summary/Keyword: Extracellular

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Retention of Endothelial Cells adhered on Polyurethane Surface under Flow Condition

  • Chang, Jun-Keun;Chang, Hyun-A;Kim, Jin-Hee;Kim, Jong-Won;Han, Dong-Chul;Min, Byoung-Goo
    • Journal of Biomedical Engineering Research
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    • v.17 no.3
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    • pp.355-364
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    • 1996
  • Construction of the stable monolayer of endothelial cells onto physicochemically modified polymeric surFace is one of the appropriate method to develop the small caliber vascular graft with the long-term patency. In this study, we constructed the monolayer of endothelial cells on the fibronectin rind the extracellular matrix-coated polyurethane surface derived from human fibroblast cells. To elucidate the adhesion strength of endothelial cells on the extracellular matrix-coated polyurethane, a laminar flow chamber apparatus was developed to exposure the shear stress on the apical membrane of ondothelial cells. Endothelial cells show the strongest adhesion after two days of seeding onto the fibronectin-coated polyurethane surface, whereas endothelial cells on the extracellular matrix derived from the human flbroblast cells show the minimal doubling time of cellular growth.

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Effects of Oxygen Free Radicals on Extracellular Glutamate Accumulation in Cultured Cells

  • Shin, Chang-Sik;Oh, Seikwan;Lee, Myung-Koo;Lee, Myung-Koo;Kim, Hack-Seang
    • Archives of Pharmacal Research
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    • v.19 no.2
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    • pp.132-136
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    • 1996
  • Exogenously applied oxygen free radical generating agent, pyrogallol, highly elevated extracellular glutamate accumulation and augmented N-methyl-D-aspartate (NMDA)-induced glutamate accumulation in cerebellar granule neuronal cells, but did not in astrocytes. Superoxide dismutase remarkably decreased the pyrogallol-induced glutamate accumulation, but either NMDA or kainate antagonists did not. In addition, pyrogallol did not affect the NMDAinduced intracellular calcium elevation. Pyrogallol partially blocked glutamate uptake into astrocytes. These results suggest that oxygen free radicals elevate extracellular glutamate accumulation by stimulating the release of glutamate as well as blocking the glutamate uptake.

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Optimum culture conditions for production of extracellular cytosine deaminase by bacellus polymyxa YL 38-3 (Bacillus polymyxa YL38-3의 세포외 cytosine deaminase 생성의 최적 배양 조건)

  • 유대식;김대현;박정문;송형익;정기택
    • Korean Journal of Microbiology
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    • v.26 no.4
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    • pp.362-367
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    • 1988
  • The strain YL 38-3, which was capable of producing extracellular cytosine deaminase, was isolated and taxonomically examined. The isolated strain was identified to be Bacillus polymyxa YL 38-3. The optimal conditions for the enzyme production from Bacillus polymyxa YL 38-3 were investigated. The enzyme production was reached maximum level in the medium containing 0.5% glucose, 0.2% beef extract, 0.5% NaCl and 0.1% $KH_{2}PO_{4}$ (pH 6.0). And the enzyme showed the highest activity when the strain YL 38-3 was cultivated at $35^{\circ}C$ for 24 gours under the initial pH 6.0. By the additions of peptone the extracellular enzyme production was inhibited, meanwhile the intracellular enzyme production was highly stimulated. It was, therefore, deduced that peptone was related to the secretion mechanism of the enzyme from this bacterial cell.

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Cloning of the gense coding for extracellular proteases from alkalophilic xanthomonas SP. JK311

  • Kim, Young-Hun;Jang, Ji-Yeon;Yeehn Yeeh;Kim, Yong-Ho;Kim, Sang-Hae
    • Journal of Microbiology
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    • v.33 no.4
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    • pp.344-349
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    • 1995
  • The alkalophilic bacterium, Xanthomonas sp. JK311, producing extracellular proteases, was isolated from soil. Xanthomonas sp. JK311 produced five extracellular proteases that are all metalloproteases. Four of them were resistant against 1% SDS. Chromosomal DNA of the Xanthomonas sp. JK311 was digested with BamHI and cloned into PUC19. Among E. coli strain HB101 transformants, a clone secreting the proteases was screened through halo formation on skim-milk agar plate and by Southern blot analysis. It had the recombinant plasmid pXEP-1 containing the 7.5 kb-BamHI DNA fragment and produced three extacellular proteases. Their protease properties corresponded to those of Xanthomonas sp. JK311.

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Properties of the Extracellular Proteins Produced by Bacillus sp. WY-60 (Bacillus sp. WY-60이 생산한 균체외 단백질의 특성)

  • Kwon, Oh-Jin;Park, Shin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.22 no.6
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    • pp.807-810
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    • 1993
  • Extracellular proteins of Bacillus sp. WY-60 were obtained, and then the properties of the isolated proteins were characterized. The proteins were composed of two kinds of protein in size. The molecular weight of the major protein was around 21,000 according to the gel filtration chromatography and SDS-polyacryamide gel electrophoresis. The amino acid composition showed that glutamic acid was a major amino acid with the concentration of 26.16mg/g. The isoelectric point of the proteins was about pH 7.5.

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STUDIES ON THE EXTRACELLULAR POLYSACCHARIDES PRODUCED BY ISOLATED DENTAL PLAQUE STREPTOCOCCI (Dental Plaque Streptococci가 생산하는 세포외 다당류에 관한 연구)

  • Chung, Tai-Young
    • The Journal of the Korean dental association
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    • v.9 no.12
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    • pp.812-818
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    • 1971
  • The present investigation describes the chemical nature of purified extracellular polysaccharides synthesized by tow resembling streptococci, Streptococcus salivarius strain SD-1 and Streptococcus mitis strain SD-9, which was isolated from human dental plaque, with the following results. 1. Extracellular polysaccharide by Streptoccus salivarius strain SD-1 is recovered mostly in Fraction I-and II-45% of the presne purification procedure, leaving trace amount in Fraction I-and II-70%. 2. The dextran is the major polysaccharides in Fraction I-and II-45% of both strains with minor amounts of levan. 3. The Fraction I-and II-45% of both strains contain glucose and fructose, which its 70% of the same fractions glucose only. 4. It appears that the glycerol was the major end product of the Smith degradation of the Fraction I-45% of both strains.

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Hepatoprotective Effect of Extracellular Polymer Produced by Submerged Culture of Ganoderma lucidum WK-003

  • Song, Chi-Hyun;Yang, Byung-Keun;Ra, Kyung-Soo;Shon, Dong-Hwan;Park, Eun-Jeon;Go, Geon-Il;Kim, Young-Hwoan
    • Journal of Microbiology and Biotechnology
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    • v.8 no.3
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    • pp.277-279
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    • 1998
  • An extracellular polymer (exo-polymer) with hepatoprotective properties was produced after a 6-day submerged mycelial culture of Ganoderma lucidum WK-003. The glutamic pyruvic transaminase (GPT) activities in the serum of intoxicated Sprague-Dawley rats were decreased from 871 to 263 by the oral administration of the exo-polymer (20 mg/kg/day) for 4 consecutive days. Rhamnose, arabinose, xylose, mannose, galactose, and glucose were found in the exo-polymer along with aspartic acid, glutamic acid, histidine, serine, glycine, arginine, alanine, tryptophan, valine, phenylalanine, isoleucine, and leucine.

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Surgical Treatment of Corneal Sequestrum with Porcine Urinary Bladder Submucosa Extracellular Matrix (ACeLL Vet® Corneal Disc) in Two Cats

  • Kim, Youngsam;Kang, Seonmi;Nam, Sunhwa;Yun, Seongjin;Seo, Kangmoon
    • Journal of Veterinary Clinics
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    • v.37 no.4
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    • pp.213-216
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    • 2020
  • Two cats were presented to the Dana Animal Hospital Eye Center and were diagnosed with corneal sequestrum through full ophthalmic examination. After lamellar keratectomy using a reusable corneal trephine blade and a crescent microsurgical knife, porcine urinary bladder submucosa extracellular matrix (UBM, ACeLL Vet® corneal disc) was applied to the corneal defects. In both cases, no corneal sequestrum recurrences were observed until 119 days and 253 days after the surgery, respectively. Porcine UBM could be recommended as a surgical scaffold for treatment of corneal sequestrum in cats.

Characterization of Bacillus cereus SH-7 Extracellular Protease

  • Yi, Hak-Kyu;Chun, Young-Jin;Kim, Han-Bok
    • Journal of Microbiology
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    • v.37 no.4
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    • pp.213-217
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    • 1999
  • An extracellular endopeptidase from Bacillus cereus SH-7 was purified to homogeneity. The protease was most active at pH 8 and $40{\circ}C$, respectively. The molecular mass of the protease was 40 kDa on SDS-PAGE, and 120 kDa by gel filtration, suggesting that the native enzyme is composed of three homogeneous subunits. The $K_m\;and\;V_{max}$ values of the protease for N-succinyl-$(Ala)_2$-Pro-Phe-p-nitroanilide were 11.11 mM and 170 nmol/mg of protein/min, respectively. The protease was also identified as a metalloprotease. The bioactivity of the SH-7 protease will need further study in the future.

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Detection of Extracellular Enzyme Activities in Various Fusarium spp

  • Kwon, Hyuk-Woo;Yoon, Ji-Hwan;Kim, Seong-Hwan;Hong, Seung-Beom;Cheon, Young-Ah;Ko, Seung-Ju
    • Mycobiology
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    • v.35 no.3
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    • pp.162-165
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    • 2007
  • Thirty seven species of Fusarium were evaluated for their ability of producing extracellular enzymes using chromogenic medium containing substrates such as starch, cellobiose, CM-cellulose, xylan, and pectin. Among the tested species Fusarium mesoamericanum, F. graminearum, F. asiaticum, and F. acuminatum showed high ${\beta}$-glucosidase acitivity. Xylanase activity was strongly detected in F. proliferatum and F. oxysporum. Strong pectinase activity was also found in F. oxysporum and F. proliferatum. Amylase activity was apparent in F. oxysporum. No clear activity in cellulase was found from all the Fusarium species tested.