Nature of the Growth Factor for the Colorless Alga Prototheca Zopfii
نویسنده
چکیده
Barker's study on the nutritive requirements of Prototheca zopfii indicated that this colorless alga fails to grow in the absence of small amounts of yeast extract. A study of the growth factor requirements of Prototheca has shown that the active constituent of yeast extract necessary for the growth of this organism is thiamin (vitamin B(1)). Thiamin can fully replace the complex yeast material and allows, in the basal medium used, a maximum cell yield in concentrations of 1-3 x 10(-7)M. Thiamin as such, however, is not essential for the growth of Prototheca zopfii. The alga can develop equally well if supplied with both the thiazole and pyrimidine constituents of this vitamin. These appear to be needed in equimolar proportions. Maximum cell yield is obtained with 3 x 10(-8)M concentrations of the two components.
منابع مشابه
Molecular characterization of Polish Prototheca zopfii mastitis isolates and first isolation of Prototheca blaschkeae in Poland.
Bovine mastitits caused by the colorless, yeast-like alga Prototheca zopfii is a serious and complex condition that results in heavy economic losses in the dairy industry, both through a substantial reduction in milk production and culling of infected animals. Based on the 18S rDNA sequence analysis, genotype-specific PCR assays have recently been developed to differentiate within the species P...
متن کاملStudies on the Metabolism of the Colorless Alga Prototheca Zopfii
The metabolism of Prototheca zopfii was investigated in an attempt to establish the specific function of its growth factor, thiamin. A study of the oxidative decomposition of various substrates by this organism demonstrated that the addition of catalytic amounts of thiamin to vitamin-deficient cells causes a pronounced stimulation in the rate of oxygen utilization during the degradation of cert...
متن کاملIn vitro activity of conventional antifungal drugs and natural essences against the yeast-like alga Prototheca.
BACKGROUND Two outbreaks of mastitis due to the yeast-like alga Prototheca zopfii recently occurred in dairy herds in Lombardia (Italy) involving 180 and 150 lactating cows, respectively. OBJECTIVES To determine the in vitro susceptibility of Prototheca isolates to conventional antifungal agents and to essential oils. METHODS Twenty P. zopfii isolated from milk during these outbreaks, six P...
متن کاملPrototheca zopfii mastitis in a herd of dairy cows.
Mastitis caused by the colourless alga Prototheca zopfii was diagnosed in 17 of 120 cows in a dairy herd. Infection occurred in animals varying from 3-14 years old and was present in one to four quarters of each cow. Nine cases were associated with clinical mastitis characterised by the presence in milk of flakes or small clots. Somatic cell counts consistent with subclinical mastitis (>500 x 1...
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ورودعنوان ژورنال:
- The Journal of General Physiology
دوره 28 شماره
صفحات -
تاریخ انتشار 1945