• 한국수산과학회지
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• 제46권6호
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• pp.901-906
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• 2013

We examined the availability of the lacZ gene (${\beta}$-galactosidase gene) as a reporter of foreign gene transfer in the cysts of Artemia franciscana (A. franciscana) to conduct a risk assessment of living genetically modified organisms (LMOs) in the marine ecosystem. The LacZ gene was transferred to decapsulated cysts by particle bombardment, and its insertion and expression were assessed by means of polymerase chain reaction (PCR) and X-gal staining. X-gal staining indicated lacZ expression in all A. franciscana examined (including the control group), which exhibited not only negative but also positive PCR amplification. Endogenous ${\beta}$-galactosidase is highly active in the whole body of A. franciscana during all stages of the life cycle. Thus, the lacZ gene is unsuitable as a reporter for foreign gene transfer in A. franciscana cysts, because it is difficult to discriminate between exogenous and endogenous ${\beta}$-galactosidase activity.

• 생명과학회지
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• 제7권3호
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• pp.228-233
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• 1997

Artemia franciscana의 cyst에서 protease를 정제하가 위해 세포를 파쇄하여 원심 분리한 후 상등액을 회수하였다. 그상등액에서 40-60% 황산암모늄을 첨가하여 침전시켜서 염을 제가한 후, Sphadex G-200 및 DEAE-Sephadex A-50 column chromatography를 하여 정제한 후 본 효소의 특성을 조사한바 그 특성은 아래와 같았다. 정제 과정을 거치는 동안, 비활성은 13.64배 증가하였고, 수율은 7%였다. 그리고 이효소는 pH 6에서는 안정하였으나, pH 8이상에서는 대부분의 활성이 실활 되었고, 최적 pH는 3.0이었다. 따라서 이 효소는 전형적인 산성 pro-tease로 판정되었다. 본 효소는 60$^{\circ}$C이상의 온도에서 대부분 실활 되었고, 최적 활성 반응 온도는 35$^{\circ}$C였다. 금속 이온의 영향을 알아본 결과, $Cu^{++}$, Z$Zn^{++}$, $Fe^{++}$가 효소의 활성을 저해하였고, 중금속 chelator인 EDTA는 반대로 효소 활성을 증가시켰다. 단백질분해효소에 특이적인저해제를 첨가하여 실험한 결과 thiol protease ingibitor인 antipain, chymostatin, leupeptin, E-64, iodoacetate등에 효과적으로 효소활성이 저해받으므로 본 효소는 acid thiol protease라 판정했다.

• Fisheries and Aquatic Sciences
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• 제15권2호
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• pp.177-181
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• 2012

To understand the effects of lower pH levels due to elevated $CO_2$ and salinity, we designed and constructed a pH-control system that included automatic $CO_2$ infusion and measured the hatching rate of a crustacean model species, Artemia franciscana. The pH-control system was cost-effective and capable of performing animal tests in which pH fluctuated around $8.0{\pm}0.1$, with the temperature around $27{\pm}0.5^{\circ}C$. Hatching rate was observed under four different pH levels (7.0, 7.3, 7.6, and untreated control) combined with three salinity ranges (15, 25, and 35 ppt). The results demonstrated that lower pH levels led to decreased hatching rates regardless of salinity, and the minimum hatching rate was detected at pH 7.0 compared to the control (pH $8.0{\pm}0.1$), supporting the idea that OA has adverse effects on hatching rates and increases the risk of juveniles being introduced in the ecosystem. In contrast, salinity changes exhibited no synergistic effects with pH and had independent effects.

• 한국양식학회지
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• 제17권2호
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• pp.151-157
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• 2004

Effects of supplementing selected fatty acids on fatty acid incorporation (17 days) , and progeny production (14 days) in Artemia franciscana (Great Salt Lake, USA) were studied. To compare with the control four diets, which differed in fatty acid composition alone contain Dunalieia tertiolecta and an emulsion either rich in OA (oleic acid, 18: 1 n-9), ARA (arachidonic acid, 20:4n-6), EPA (eicosapentaenoic acid,20:5n-3), or DHA (docosahexaenoic acid, 22:6n-3). Each of these emulsions was supplemented at a ratio of 20 % of the daily dose of D. tertiolecta (% algal dry weight). The initial OA and ARA values were 33.5 and 1.7 mg/g DW of freshly-hatched nauplii, respectively. After 11 days of feeding, these values increased to 38.8 and 7.6 mg/g DW in Artemia receiving the fatty acid sup-plement rich in each of the respective fatty acids. After 14 days, the levels were almost doubled, reaching 62.8 and 13.4 mg/g respectively. On EPA supplementation, its level after 11 days of feeding was 14.3 and 17.3 mg/g in male and female, respectively and was 16.0 and 23.1 mg/g in the male and female after 14 days, respectively. The EPA accumulated more in the body (39.1 mg/g) than in ovisac (16.9 mg/g). In the DHA supplementation group also, DHA levels after 11 days of feeding were 3.1 and 5.5 mg/g in male and female, respectively. After 14 days, the DHA level continued to increase in male. but slightly decreased to 4.6 mg/g in female. It was not richer in ovisac (2.6 mg/g) than in the remaining body of female (4.6 mg/g). In conclusion, fatty acids supplied by a lipid emulsion as a supplement to the algal diet are well incorporated in the adult Artemia. Apart from being an extra source of energy, these emulsions may function as source of HUFA which may play an essential role for growth and progeny production (fecundity) of Artemia.