• 한국미생물·생명공학회지
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• 제23권4호
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• pp.432-438
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• 1995

The intracellular alginase from Vibrio sp. AL-145 was purified by ion chromatography on DEAE-Cellulose column, Q-Sepharose column, and gel filtration on Sephadex G-100 column. The optimum pH and temperature for the activity of the purified intracellular enzyme were 8.0 and 37$\circ$C, respectively. The enzyme was stable at the pH range of 7.5-8.5, and at 30$\circ$C for 30 min. The molecular weight of the intracellular enzyme was estimated to be about 23, 000 daltons by SDS-polyacrylamide gel electrophoresis. NaCl was required for enzyme activity and the optimum concentration was 0.5 M. The activity of intracellular enzyme was inhibited by Co$^{2+}$, Hg$^{2+}$, Zn$^{2+}$, 0-phenanthroline, $\rho$-CMB, EDTA and iodoacetate, and stimulated by Ca$^{2+}$, L-cysteine and 2-mercaptoethanol. This enzyme was an alginase specifically degrading alginic acid.

• 대한의생명과학회지
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• 제11권3호
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• pp.301-305
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• 2005

MR spectroscopy of intracellularly located $^{133}Cs$ has been used to monitor the uptake of Gd-EOB-DTPA by the isolated rat liver. As shown by ${31}P$ spectroscopy, accumulation of $^{133}Cs$ ions in hepatocytes does not produce detectable effects on the metabolism. The hepatic internalization of Gd-EOB-DTPA was followed by the paramagnetic relaxation enhancement of the intracellular $^{133}Cs$ ions, and confirmed by parallel quantitations of Gd and Cs run by inductively coupled plasma analysis of liver samples and aliquots of perfusate. Two peaks are observed at -22.0 and -23.5 ppm, with respect to the line of the external reference arbitarily set to 0 ppm. Upon rinsing of the extracellular compartment with regular K-H free of CsCl, the high-field resonance disappears within 20min. The intracellular concentration was confirmed by ICP, which gives a $Cs^+$ content of $22.0\pm3.5mM$. The relaxation data significantly underestimate the Gd content, suggesting a potential compartmentation of $Cs^+$ and the contrast agent.

• The Korean Journal of Physiology
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• 제19권1호
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• pp.49-59
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• 1985

The effects of anions on net accumulation of $(\rho-aminohippuric\;acid)$(PAH) were studied in rabbit kidney cortical slices. Experiments were carried while varying the major anionic composition of the incubation medium(replacement of $Cl^-$ by isethionate and $SCN^-$). The total replacement of $Cl^-$ with isethionate, $SO_4\;^{2-}$ and $SCN^-$ in the incubation medium decreased the 60-min slice-to-medium concentration(S/M) ratio of PAH to 60%, 40% and 50% of control value, respectively. The degree of inhibition in PAH accumulation by the replacement of isethionate and $SCN^-$ was increased with increasing of both preincubation and incubation time. The influence of isethionate and $SCN^-$ on PAH uptake was fully reversible. Both isethionate and $SCN^-$ increased the apparent Km value significantly with no change on the apparent Vmax value, suggesting a competitive inhibition on PAH uptake. And the inhibitory effect of $SCN^-$ on PAH uptake decreased with increase of pH in the incubation medium while that of isethionate increased with increase of pH. Intracellular water content, intracellular electrolyte concentration and oxygen consumption were not influenced by the replacement of $Cl^-$ with isethionate or $SCN^-$ in the incubation medium. These results suggest that both $isethionate^-$ and $SCN^-$ inhibit the PAH uptake by binding to some site necessary for normal PAH transport without affecting the cellular viability.

• 한국물환경학회지
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• 제22권3호
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• pp.513-520
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• 2006

The effect of chlorination on disinfection byproducts (DBPs) production from bloom-forming freshwater algae including 7 strains of cyanobacteria and 6 strains of diatoms was investigated. The release and degradation of hepatotoxin (microcystins) by the chlorination on Microcystis under differential condition of the chlorination time and dose were also investigated. The disinfection byproducts formation potentials (DBPFP) of cyanobacterial species and diatoms were ranged from 0.017 to $0.070{\mu}mol\;DBPs/mg$ C and from 0.129 to $0.708{\mu}mol\;DBPs/mg$ C respectively. Among three major groups of DBPs, haloacetonitrils (HANs) was major product in most test strains except Aphanizomenon sp. and Oscillatoria sp. Haloacetic acids (HAAs) was less than 5 % of total DBPs. Chloroform and dichloroacetonitril (DCAN) were dominant compounds in trihalomethanes (THMs) and HANs respectively. After 4 hours chlorination of toxic Microcystis aeruginosa under the dose range of 0.5 to $10mg\;Cl_2/L$, the concentration of intracellular microcystins decreased, but dissolved dissolved microcystins concentration increased with the treatment of more than $3mg\;Cl_2/L$. However the total amount of microcystins was almost constant even at $10mg\;Cl_2/L$ of chlorination. To conclude, our results indicate that the chlorination causes algal cell lysis and release of intracellular microcystins in the intact form to surrounding waters.

• 한국미생물·생명공학회지
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• 제17권3호
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• pp.247-251
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• 1989

여러가지 염이 sisomicin 발효에 미치는 영향에 대해 살펴본 결과, CoCl$_2$만이 항생물질 생성의 대사반응에 cofactor로서 작용하였으며 16.8 $\mu$M에서 최대항생물질의 수율이 얻어졌다. 한편, 앞의 경우보다 훨씬 높은 염농도에서 ZnSO$_4$, KH$_2$PO$_4$, FeSO$_4$그리고 MgSO$_4$가 각각 발효배지에 첨가되었다. ZnSO$_4$와 KH$_2$PO$_4$는 전혀 효과가 없었으나 FeSO$_4$는 약간 항생물질 수율의 향상을 가져왔다. 그러나 MgSO$_4$의 경우, 매우 높은 염농도에서도 균체생육의 저해가 약간 일어났으며, 최종 항생물질의 수율은 100% 이상 증가되었다. 이러한 결과는 부분적으로 발효 중 균체내에 생성된 항생물질이 균체외로 유출되는 효과가 증진된 것에 기인한다.

• The Korean Journal of Physiology and Pharmacology
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• 제8권5호
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• pp.259-264
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• 2004

Cytolysin produced by Vibrio vulnificus has been incriminated as one of the important virulence determinants in V. vulnificus infection. Ion selectivity of cytolysin-induced pores was examined in a CPAE cell, a cell line of pulmonary endothelial cell, using inside-out patch clamp techniques. In symmetrical NaCl concentration (140 mM), intracellular or extracellular application of cytolysin formed ion-permeable pores with a single channel conductance of $37.5{\pm}4.0$ pS. The pore currents were consistently maintained after washout of cytolysin. Replacement of $Na^+$ in bath solution with monovalent ions $(K^+,\;Cs^+\;or\;TEA^+)$ or with divalent ions $(Mg^{2+},\;Ca^{2+})$ did not affect the pore currents. When the NaCl concentration in bath solution was lowered from 140 to 60 and 20 mM, the reversal potential shifted from 0 to -11.8 and -28.2 mV, respectively. The relative permeability of the cytolysin pores to anions measured at $-40\;mV\;was\;Cl^-\;=\;NO_2^-\;{\geq}\;Br^-\;=\;I^-\;> \;SCN^-\;>\;acetate^-\;>\;isethionate^-\;>\;ascorbic acid^-\;>\;EDTA^{2-},$ in descending order. The cytolysin-induced pore current was blocked by $CI^-$ channel blockers or nucleotides. These results indicate that V. vulnificus cytolysin forms anion-selective pores in CPAE cells.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 1997년도 학술발표회
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• pp.17-17
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• 1997

We investigated the relationship between the voltage-operated calcium channel current and the corresponding [Ca$^{2＋}$]i change (Ca$^{2＋}$-transient) in guinea-pig gastric myocyte. Fluorescence microspectroscopy was combined with conventional whole-cell patch clamp technique and fura-2 (80 $\mu$M) was added into the CsCl-rich pipette solution.(omitted)

• The Korean Journal of Physiology
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• 제26권1호
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• pp.27-35
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• 1992

We used the whole cell patch clamp technique to examine the ionic basis for the tail current after depolarizing pulse in single atrial myocytes of the rabbit. We recorded the tail currents during various repolarizations after short depolarizing pulse from a holding potential of -70 mV. The potassium currents were blocked by external 4-aminopyridine and replacement of internal potassium with cesium. The current was reversed to the outward direction above +10 mV. High concentrations of intracellular calcium buffer inhibited the activation of the current. Diltiazem and ryanodine blocked it too. These data suggest that the current is activated by intracellular calcium released from sarcoplasmic reticulumn. When the internal chloride concentration was increased, the inward tail current was increased. The current was partially blocked by the anion transport blocker niflumic acid. The current voltage curve of the niflumic acid sensitive current component shows outward rectification and is well fitted to the current voltage curve of the theoretically predicted chloride current calculated from the constant field equation. The currents recorded in rabbit atrial myocytes, with the method showing isolated outward Na Ca exchange current in ventricular cells of the guinea pig, suggested that chloride conductance could be activated with the activation of Na/ca exchange current. From the above results it is concluded that a chloride sensitive component which is activated by intracellular calcium contributes to tail currents in rabbit atrial cells.

• Journal of Plant Biology
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• 제33권4호
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• pp.315-320
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• 1990

We investigated the interaction of auxin and Ca2+ on coleoptile segment elongation in seedlings of Zea mays L. Seedlings imbibed and raised either in the presence of 10 mM CaCl2 (HC), or in the absence of Ca2+ (LC) were used. Exposure to 10-5M auxin of coleoptiles from either HC or LC seedlings resulted in strong promotion of elongation. However, longer latent period (90 min) of the auxin effect was observed in HC than in LC seedlings (20 min). The length of latent period observed in HC coleoptiles was proportional to the concentration of CaCl2. The latent period of auxin effect observed in HC seedlings was abolished by pretreatment of the coleoptiles with TMB-8 which inhibits IP3-induced Ca2+ release from the tonoplasts. In segments of LC seedlings, the promotive effect of IAA (10-5M) was abolished by treatment with 5 mM calcium but was reversible upon treatment of the segments with 5 mM EGTA. These results suggest that the effect of auxin on coleoptile elongation is closely related to intracellular Ca2+ level.

• 한국자원식물학회지
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• 제27권6호
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• pp.714-719
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• 2014

This study investigated DNA damage protection and anti-inflammatory activity of different solvent fractions from Aruncus dioicus var. kamtschaticus (A. dioicus) aerial parts water extract. As for DNA damage protection, distilled water ($H_2O$) fraction displayed the most powerful protection for DNA damage at a concentration of 1 mg/ml. As for anti-inflammatory activity, dichloromethane ($CH_2Cl_2$) fraction exhibited the highest NO inhibition activity, ranging from 61% to 19% ($10-40{\mu}g/ml$). Furthermore, the levels of pro-inflammatory cytokines mRNA expressions and intracellular reactive oxygen species (ROS) were employed to verify the anti-inflammatory activity of the $CH_2Cl_2$ fraction on further researches. It could be concluded that A. dioicus had a significantly effect of DNA damage protection and anti-inflammatory activity which also as an essential edible vegetable and medicinal species.