• Journal of Microbiology and Biotechnology
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• 제11권1호
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• pp.72-78
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• 2001

It is possible ot prepare protoplasts of the zygomycete fungus, Phycomyces blakesleeanus, by digesting the cell wall of spore germlings with commercially available chitinase and chitosanase. However, the cells without any cell walls immediately form large aggregates, and thus, it is difficult to isolate the individually separated protoplasts. Inherent problem with the formation of aggregates in preparing protoplasts could be solved by the use of bovine serum albumin (BSA). As a result, we were able to prepare a large number of single protoplsts quickly and easily. We took time-lapse photomicrographs of the formation of protoplasts, and found that there were certain regions of the cell wall of spore germlings that were sensitive to chitinase and chitosanase, although the cell wall of the original spores is known to be insensitive to these enzymes. There are two kinds of cell walls on a spore germling; one with a bound wheat germ agglutinin (WGA), and the other a bound concanavalin A (ConA). Furthermore, only cells with walls which had bound WGA were able to regenerate, while those with walls with bound ConA were not able to regenerate.

• 한국식품과학회지
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• 제11권2호
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• pp.105-111
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• 1979

재래식 메주로 부터 분리(分離)한 Phycomyces속(屬)의 포자낭병의 지질조성(脂質組成)을 분석(分析)하여 다음과 같은 결과(結果)를 얻었다. 1. 건체중(乾體中)의 지질(脂質)을 18.2%로서 그 조성(組成)은 중성지질(中性脂質)이 69.2%, 당지질(糖脂質)이 24.3% 그리고 인지질(燐脂質)이 6.5%였다. 2. 중성지질(中性脂質)의 구성성분(構成成分)은 carotene,탄화수소(炭化水素), estrified sterol, 지방산(脂肪酸) ester, triglyceride, 유리지방산(遊離脂肪酸), 유리(遊雌) sterol등이고 주성분(主成分)은 유리지방산(遊離脂肪酸)과 triglyceride로서 각각 45.6%와 30.9%를 차지하였다. 3. $AgNO_3-TLC$에 의한 방법(方法)으로 triglyceride에서 12개(個), diglyceride에서 8개(個)의 lipid molecular species를 분별(分別)하였다. 4. 총(總) 지질(脂質)의 주지방산(主脂肪酸)은 stearic, linoleic. arachidic, linolenic acid이고 유리지방산(遊離脂肪酸)의 주지방산(主脂肪酸)은 stearic, linoleic, arachidic acid 등이었다.

• Journal of Photoscience
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• 제1권1호
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• pp.69-73
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• 1994

Sporangiophores (spphs) of Phycomyces blakesleeanus are positively phototropic to unilateral visible (blue) light over a range of fluence rates 10$^{-9}$ to 1 W/m$^2$. The maximal bending angle is always 70-75$\circ$ from the vertical. Many mutants with abnormal phototropism have been isolated. Complementation tests revealed that the genetic grouping is completely consistent with the phenotypic classification scheme, based on sensory responses other than those to light. The spph of the piloboloid mutant, the growth zone of which gradually ceases elongation but expands spherically, and the $\beta$-carotene-overproducing mutant show negative phototropism, in contrast to the wild type spph. We hypothesized that the phototropic orientation of spph is determined by the ratio of the maximal light fluenee rate at the proximal side to that at the distal side of the spph. Based on this hypothesis, we found that the maximal bending angle was larger in thin spphs than in thick ones, and larger in spphs containing smaller amount of $\beta$-carotene than in carotene-rich spphs. In addition to our hypothesis, gravitropic experiments revealed that the maximal bending angle of the wild type spph results from a balance among positive phototropism, negative gravitropism, and the optical properties of the spph. For further advancement of this study, we developed a mutant with a high proportion of uninucleate spores, and designed an efficient microinjection method for obtaining transformants.

• 농업과학연구
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• 제36권1호
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• pp.27-40
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• 2009

털곰팡이 야생종(DEL)과 5균주의 돌연변이 (A56, C9, C47, C111, G5)를 명소에서 6일간의 생장을 조사한 결과 생육일수에 따른 생 중량의 증가나 건물 중의 증가는 공시한 6균주가 동일한 경향을 보여 돌연변이 균주간의 차이는 인정할 수 없었다. 그러나 생중량과 건물중의 패턴 변화는 큰 차이를 보여 공시 균주 모두 배양 후 3일 이후부터는 건물 중의 증가는 뚜렷하지 않으나 생중량만은 계속 증가하였다. 이러한 사실은 배양 3일 이후에 형성되는 대형포자낭병의 발생과 굴광성이 건물생장에 의한 것이 아니라 오로지 수분유입팽창력 따른 편차생장 때문임을 강하게 시사하고 있다. 균주 간에서 보이는 파장별 굴광성의 감수성은 A56과 DEL, G5에서 가장 강하게 나타나 적색광의 파장역에서도 굴광성을 보이는 반면 C9 과 C47은 청색광 영역에서만 약한 감수성을 나타내었다. 그리고 C111은 전혀 굴광성을 나타내지 않았다. 이들 대형포자낭의 굴광성에 대한 광 감수성과 미소포자낭병의 발생 간에 어떤 길항적인 관계가 성립됨이 확인되었다. 즉 6균주 모두 대형포자낭의 굴광성이 청색광역에서 강하게 나타나다가 적색광역에선 그 반응이 감소되면서 미소포자낭병의 발생이 오히려 증가되었다. 이러한 결과로 미루어 볼 때 이들 대형포자낭의 발생 및 굴광성과 미소포자낭병의 발생 간에는 광파장의 인식인자(광수용체)가 하나의 공통적 기작에 의해 조절된다는 사실을 강하게 시사했다.

• 대한수의학회지
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• 제36권2호
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• pp.389-394
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• 1996

This study was carried out to determine the causative agent of dermatophytosis in 7 horses, and to examine the skin mycofloras on 84 healthy and 7 diseased horses which were derived from Jae-ju and Kyonggi, Korea in 1994~1995. Specimens of hair and scale were collected from skin lesions(or normal skins) and inoculated directly on potato dextrose agar and mycobiotic agar. These agar plates were incubated at $25^{\circ}C$ for 2 weeks. Growing fungi were isolated and identified by the morphological and nutritional characteristics. Lesions were found on the hind legs of an infected horses and each lesion was round or oval(1~4 cm) in shape accompanied by severe itching. The causative agent of the 7 equine dermatophytosis was identified as Trichophyton equinum. The skin mycofloras were Penicillium(69.0%), Aspergillus(63.2%), Cladosporium(51.7%), Fusarium(31.0%), Mucor(28.7%), Absidia(18.4%), Alternaria(17.2%), Acremonium(11.5%), Paecilomyces and Phycomyces(6.9%), Rhizopus(5.6%), Trichoderma(4.6%), Scopulariopsis and Trichophyton(3.5%), Beauveria(2.3%), Tritiracheum, Sporothrix, Curvularla, Aureobasidium and Chaetomium(1.2%), and Yeast(27.6%).

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권4호
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• pp.263-274
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• 2000

Carotenoids are widely distributed natural pigments which are in an increasing demand by the market, due to their applicatins in the human food, animal feed, cosmetics, and pharmaceutical industries. Although more than 600 carotenoids have been identified in nature, only a few are industrially important (${\beta}$-carotene, astaxanthin, lutein or lycopene). To date chemical processes manufacture most of the carotenoid production, but the interest for carotenoids of biological origin is growing since theire is an increased public concern over the safety of artificial food colorants. Although much interest and effort has been devoted to the use of biological sources for industrially important carotenoids, only the production of biological ${\beta}$-carotene and astaxanthin has been reported. Among fungi, several Mucorales strains, particularly Blakeslea trispora, have been used to develop fermentation processes for the production of ${\beta}$-carotene on almost competitive cost-price levels. Similarly, the basidiomycetous yeast Xanthophyllomyces dendrorhous (the perfect state of Phaffia rhodozyma), has been proposed as a promising source of astaxanthin. This paper focuses on recent findings on the fungal pathways for carotenoid production, especially the structure and function of the genes involved in the biosynthesis of carotenoids in the Mucorales. An outlook of the possibilities of an increased industrial production of carotenoids, based on metabolic engineering of fungi for carotenoid content and composition, is also discussed.