• Journal of Microbiology and Biotechnology
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• v.18 no.12
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• pp.1958-1965
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• 2008

A denitrifying polyphosphate-accumulating bacterium (YKP-9) was isolated from activated sludge of a 5-stage biological nutrient removal process with step feed system. This organism was a Gram-negative, coccus-shaped, facultative aerobic chemoorganotroph. It had a respiratory type of metabolism with oxygen, nitrate, and nitrite as terminal electron acceptors. The 16S rRNA gene sequence of strain YKP-9 was most similar to the 16S rRNA gene sequence of Paracoccus sp. OL18 (AY312056) (similarity level, 97%). Denitrifying polyphosphate accumulation by strain YKP-9 was examined under anaerobic-anoxic and anaerobic-oxic batch conditions. It was able to use external carbon sources for polyhydroxyalkanoates(PHA) synthesis and to release phosphate under anaerobic condition. It accumulated polyphosphate and grew a little on energy provided by external carbon sources under anoxic condition, but did neither accumulate polyphosphate nor grow in the absence of external carbon sources under anoxic condition. Cells with intracellular PHA cannot accumulate polyphosphate in the absence of external carbon sources under anoxic condition. Under oxic condition, it grew but could not accumulate polyphosphate with external carbon sources. Based on the results from this study, strain YKP-9 is a new-type denitrifying polyphosphate-accumulating bacterium that accumulates polyphosphate only under anoxic condition, with nitrate and nitrite as the electron acceptors in the presence of external carbon sources.

• Journal of Periodontal and Implant Science
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• v.31 no.3
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• pp.543-554
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• 2001

치주조직 재생을 도모하기 위한 전통적인 시술방법으로 여러가지 골이식재를 이용한 골이식술이 이용되고 있다. 이번 실험의 목적은 골형성을 위한 재료로 Calcium Polyphosphate(CPP)를 사용하여 비글견에서의 조직 반응과 골유도성을 보는 것이고 또한 다른 이식재들간에 신생골의 형성에 어느정도 영향을 주는 가를 알아보는 것이다. 이번 실험에 사용된 CPP는 무수 $Ca(H_2PO_4)$를 condensation하여 무결정의 $Ca(PO_3)_2$를 얻고 이를 용율하고 냉각시킨 후 분쇄하여 얻은 것으로 3세된 비글견에 이식하여 관찰하였다. 조직학적으로 CPP granule의 경우는 키토산이나 $Na_2O$를 넣은 경우 모두 bone 의 ingrowth가 관찰되었고 다른 섬유조직의 개재를 볼수 없었다 동결탈회건조골을 넣은 경우에는 주위로 골형성 보이지 않았고 단지 섬유성 조직이 관찰 되었다. 아무것도 넣지 않은 경우에 비해서 동결탈회건조골이나 키토산, $Na_2O$를 넣은 CPP granules 경우에 더 많은 비율로 신생 골의 양이 나타나는 것을 볼수 있었다. 아무것도 넣지 않은 대조군과 이식재를 넣은 군간에는 유의성이 있는 것으로 나타났고(p<0.05). 또한 CPP granules with chitosan과 CPP granules with $Na_2O$ 사이에는 신생골의 형성에 유의성이 없었다. 이것으로 보아 CPP granules with chitosan과 CPP granules with $Na_2O$는 모두 골유도성이 있고 신생골의 형성을 촉진하므로 치주질환으로 인한 골결손 부위에 사용할 수 있는 재료로 우수한 특성을 지닌다고 사료된다.

• Applied Microscopy
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• v.26 no.4
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• pp.389-399
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• 1996

In order to understand the morphological differences between two different organic loadings by its upstream, and to compare with other algal groups with references, the fine structure of blue-green algae, Microcystis aeruginosa Kitzing, taken from two branches, Tongbok and Bosung stream of Lake Chuam, Korea pennisula was examined. It showed extinct differences in most physicochemical factors between both branches, except water temperature and pH values. The concentrations of total phosphorus in Tongbok branch were twice as those of Bosung. M. aeruginosa cells were enumerated totally $1.2X10^4cells/ml$ and these individuals in branch of Tongbok were close to two times as much as Bosung. In light and electron microscopy, natural M. aeruginosa colonies formed irregular shape and non-directional array in amorphous matrix. They were consisted of many kinds of cells, youngs or olds in cell division, solitary, and various size of cells. Each cell ranged from 2.61 to $5.40{\mu}m$ in diameter, and averaged as $3.54{\pm}0.19{\mu}m$. In cytoplasm, they contained a number of inclusions in various size, shape and appearances. Among them, polyhedral bodies or carboxysomes, a structured granules, photosynthetic lamellae or thylakoids, and gas vacuoles were prominent and easy to recognize. Although it was failed to find the definable morphological variations in the ultrastructure of M. aeruginosa in terms of algal habitual environments, some useful characters were founded, outer layer of cell wall, polyhedral bodies and gas vacuoles, in blue-green algal classification and taxonomy.