Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| immunohistochemistry combined with periodic acid-schiff for bovine mammary gland with protothecal mastitis. | immunohistochemistry (ihc) of bovine cytokeratin combined with periodic acid-schiff (pas) was applied to study the pathogenesis, localization and distribution of prototheca zopfii in bovine mammary protothecosis. the standard immunohistochemical procedure using anti-bovine cytokeratin was employed before and after pas staining to optimize this combined method. the best results were obtained when ihc procedures were performed first. most of the epithelial cells reacted strongly with the pancytoke ... | 2001 | 11440309 |
| bovine mastitis due to prototheca zopfii: clinical, epidemiological and pathological aspects in a brazilian dairy herd. | the clinical, epidemiological and pathological aspects of protothecal mastitis in a brazilian dairy herd are described. prototheca zopfii infection was diagnosed in 11 of 121 milking cows. clinical mastitis refractory to usual therapy was observed in 7 cows. several environmental conditions conducive to the growth of prototheca spp., such as wetness, muddiness and the presence of organic material, were present in the dairy. improper milking practices and insanitary infusion of the intramammary a ... | 2001 | 11770201 |
| stimulatory effect of procaine on the growth of several microalgae and cyanobacteria. | procaine has been used to stimulate plant growth and it has been noted that it also promotes growth of microorganisms. the effect of procaine hydrochloride concentration on the growth rates of several species of microalgae and cyanobacteria was studied under both photoautotropic and heterotrophic growth conditions. procaine hydrochloride was added to cultures at concentrations over the range 0.01-1000 mg l(-1). a stimulating effect of procaine hydrochloride on photoautotrophic growth was observe ... | 2000 | 10714957 |
| nutrition and phylogeny of predacious yeasts. | yeast predation was studied with respect to the range of its distribution among ascomycetous yeasts, the range of yeast species that can be affected, and nutritional aspects of the phenomenon. the yeasts identified as predators belong to the saccharomycopsis clade as defined on the basis of rdna sequence relatedness. the 11 recognized species in the clade, plus three undescribed but related candida species, were shown to be incapable of utilizing sulfate as sole source of sulfur, and all but two ... | 2000 | 10913970 |
| evaluation of the susceptibility of prototheca zopfii to milk pasteurization. | protothecosis has been reported in humans (gastroenteritis, bursitis, etc.) and in many other animal species. bovine mastitis represents the main form of occurrence of protothecosis in cattle. milk as well as dairy products, when contaminated with prototheca spp., represent a potential means of transmission of this zoonosis. the purpose of this study was to evaluate the susceptibility of forty prototheca zopfii strains isolated from milk from intramammary infections in dairy cows and also from b ... | 1999 | 10822507 |
| [individual animal risk factors for prototheca mastitis in cattle]. | risk factors for mastitis caused by prototheca zopfii were determined in a retrospective case control study. 248 cows culled for protothecal mastitis in a large dairy herd were included in the study. the diseased cows were compared to their non affected herdmates in respect to age, stage of lactation, production and milk composition. the effect of previous cases of mastitis during the same lactation or in previous lactations and the effect of antibiotic pretreatment were determined in a split ud ... | 1999 | 10547928 |
| identification of prototheca from bovine mastitis in denmark. | in the present study, algal isolates recovered during the period 1991 through 1996 from danish cases of bovine mastitis were characterized and identified. sixteen isolates of prototheca were obtained, all of which were identified as prototheca zopfii according to assimilation pattern, absence of capsules and resistance to clotrimazole. | 1998 | 9637271 |
| bovine mammary protothecosis due to prototheca zopfii. | mastitis due to prototheca zopfii was diagnosed in three of 28 cows in a dairy herd. as two cows continued to shed algae after 45 days they were slaughtered and organs were examined by cultivation, histology, immunohistochemistry and electron microscopy. algae were restricted to the mammary glands and regional lymph nodes in which a granulomatous inflammation was seen. algae were predominantly seen in macrophages but neutrophils also contained organisms. in macrophages both sporangiospores and s ... | 1998 | 9776819 |
| epidemiologic study of environmental sources in a prototheca zopfii outbreak of bovine mastitis. | bovine mastitis represents the main form of occurrence of protothecosis in animals. the detection of mastitis caused by prototheca sp. indicates a serious problem which can affect an entire herd. the purpose of this study is to explain some aspects of the epidemiology of mastitis due to prototheca zopfii with the evaluation of the presence of these microorganisms in samples collected from potential sources in the dairy herd. this study was performed during a prototheca zopfii outbreak of clinica ... | 1997 | 9299756 |
| bovine mastitis due to algae of the genus prototheca. | protothecosis was described in many animals, with bovine mastitis being the main form. the increasing number of isolations of prototheca spp. from bovine mastitis cases indicates the need of a detailed evaluation of this problem. besides this, these algae do not respond to treatment with the antimicrobians most frequently applied, leading to elimination of the affected animals, as the best method to control the disease. in two dairy farms in the state of são paulo, brazil, a total of 155 lactati ... | 1996 | 8751827 |
| universal fungus-specific primer systems and group-specific hybridization oligonucleotides for 18s rdna. | we designed two primer systems that amplify a fragment of the gene coding for the small ribosomal subunit (18s rrna). a broadly reactive, yet fungus-specific, primer cocktail comprises two previously published primers, tr1 and tr2, which specifically amplify dermatophytes, and two newly designed primers, ca1 and af2, which specifically amplify candida and aspergillus respectively. this primer cocktail amplifies a dna fragment of approximately 578 basepairs (bp) in length (from position 838 to 14 ... | 1996 | 8786753 |
| pathogenicity of yeasts and algae isolated from bovine mastitis secretions in a murine model. | the pathogenicity of strains of yeasts and algae isolated from bovine mastitis secretions was evaluated in immunosuppressed mice. strains of candida tropicalis (n = 3) were the most pathogenic, but all strains of geotrichum capitatum (n = 5) and the colourless alga prototheca zopfii (n = 5) were also lethal to mice at the highest dose of 1 x 10(7) cfu per mouse. reisolation of the inoculated micro-organisms and the occurrence of histopathological lesions within organs of mice challenged with 1 x ... | 1994 | 7845414 |
| mycotic and algal bovine mastitis in denmark. | a one-year examination of mammary secretions (n = 2,896) from danish cattle with clinical or subclinical mastitis revealed 45 strains of fungi and algae. the strains originated from 44 mammary secretions of 42 cows in 40 herds. the following species of fungi were identified: candida catenulata (n = 2), candida kefyr (n = 6), candida krusei (n = 17), candida rugosa (n = 6), candida tropicalis (n = 3), candida valida (n = 1), geotrichum capitatum (n = 5). the algal species prototheca zopfii was de ... | 1994 | 8068305 |
| disseminated protothecosis caused by prototheca zopfii in a cow. | 1994 | 8140719 | |
| [udder compatibility of tetramisole and levamisole hydrochloride and suggestion for the prescription of their intramammary use in cattle against prototheca zopfii]. | preparations with 4 percent tetramisole or levamisole hydrochloride were compatible in the mammary gland after application up to 40 ml/quarter (4 mg/kg body mass) for up to 6 milking times. 100 ml of the preparations were also clinically compatible in a single quarter (10 mg/kg body mass) on several days. after intramammary application of 30 ml/quarter (3 mg/kg body mass) prototheca suppressing values in milk serum were evident for at least 6 hours. one application of 200 ml in one quarter has c ... | 1993 | 8216186 |
| [experimental prototheca mastitis in cattle and therapy with tetramisole hydrochloride]. | in one cow all 4 quarters were infected with 2 x 10(8) germs of prototheca zopfii each. 2 quarters of it were treated over 6 subsequent milking times with 20 ml tetramisole hydrochloride (4 mg/kg body mass) in each case. clinical symptoms diminished within 3-24 hours after the first application in comparison with the control quarters distinctly. macroscopic alterations in the treated quarters could be found for a short time only, whereas they were evident in the control quarters for up to 2 days ... | 1993 | 8216187 |
| [pilot study of the occurrence of prototheca in fecal samples of horses]. | fecal samples of 146 horses were culturally investigated for occurrence of prototheca spp. using a selective medium, developed by pore (1973). prototheca zopfii could be isolated in monoculture from 9 fecal samples (6.2%). the results of this pilot study show that horses too can harbour and shed prototheca spp. in variable frequency. | 1993 | 8216189 |
| clavispora opuntiae and other yeasts associated with the moth sigelgaita sp. in the cactus pilosocereus arrabidae of rio de janeiro, brazil. | clavispora opuntiae was the prevalent yeast associated with the feeding sites of sigelgaita sp. larvae in the cactus pilosocereus arrabidae. also associated with this habitat were candida sonorensis, pichia cactophila, pichia barkeri, candida sp. a, geotrichum sp., geotrichum sericeum and the yeast like organisms prototheca zopfii and acremonium sp. atypical yeast biotypes that may represent new species of pichia, sporopachydermia and candida were isolated. mating types of clavispora opuntiae we ... | 1992 | 1285643 |
| the medically important yeasts present in clinical specimens. | in an effort to determine the yeast species present in clinical specimens obtained from patients attending a busy saudi hospital, the present study was undertaken. more than 1614 yeasts were isolated in culture from pathologic specimens of over 1303 patients with diverse clinical conditions. organisms identified in 22 species of eight general included: candida albicans, c. parapsilosis, c. tropicalis, c. krusei, c. lipolytica, c. guilliermondii, c. pseudotropicalis, c. pinotolopesii, c. humicola ... | 1992 | 17589130 |
| isolation of prototheca zopfii from a finger. case report and review of the literature. | prototheca zopfii, an alga-like organism, was isolated from subungual material in a patient with onycholysis. this organism seldom causes human infections. clinical and laboratory aspects are described. the literature is reviewed. | 1991 | 1659090 |
| in vitro susceptibility of prototheca spp. to gentamicin. | one hundred strains of prototheca zopfii, prototheca wickerhamii, prototheca moriformis, prototheca stagnora, and prototheca ulmnea; five strains of chlorella protothecoides; and two strains of candida albicans were obtained from a number of different clinical and environmental sources and were tested for their in vitro susceptibility to the antibacterial agent gentamicin. all prototheca strains were susceptible to gentamicin at concentrations between 0.3 and 0.9 micrograms/ml. a modified macrob ... | 1991 | 1804021 |
| prototheca zopfii: natural, transient, occurrence in pigs and rats. | domestic swine faeces and fresh faeces from trapped barnyard rats were heavily contaminated with prototheca zopfii, a cause of dairy cow mastitis. when the pigs and rats were maintained on prototheca-free diets, the transient intestinal population of p. zopfii decreased precipitously and disappeared. when combined with the information that other farm animals excrete p. zopfii, it was concluded that contaminated animal feed may be the source of large numbers of p. zopfii in the farm environment. ... | 1988 | 3278239 |
| occurrence of prototheca zopfii, a mastitis pathogen, in milk. | prototheca zopfii was isolated from cow-composite milk and bulk tank milk by a new selective prototheca enrichment method. repeated testing of cow-composite milk from individual cows resulted in p. zopfii isolation data indicating a strong statistical correlation of p. zopfii with specific cows. prototheca sp. were isolated from the milk of 31 of 79 cows in a single herd, and contamination was discounted as the source. prototheca sp. were also recovered from 28 of 787 bulk tank milk samples from ... | 1987 | 3439020 |
| prototheca zopfii isolated from a patient with olecranon bursitis. | prototheca zopfii was isolated from a patient with olecranon bursitis. olecranon bursitis caused by prototheca is a distinct clinical entity. recognition of this infection was made by observing characteristic organisms in tissue and subsequent isolation of the organism. | 1987 | 3816130 |
| synthesis of beta-glucans in prototheca zopfii. evidence for the existence of a glycoprotein primer. | membrane preparations from the non-photosynthetic alga prototheca zopfii incorporate glucose from udp-[3h]glucose into the trichloroacetic-acid-insoluble fraction and the polysaccharides insoluble in hot alkali. time course and pulse-chase experiments indicate that the acid-insoluble fraction was a precursor of the alkali-insoluble fraction. isolation of 3h-labeled membrane or soluble fraction showed that only membrane fractions were able to transfer radioactivity into polysaccharides. treatment ... | 1987 | 3816792 |
| synthesis of beta-glucans in prototheca zopfii. isolation and characterization of the glycoprotein primer. | when prototheca zopfii cells were pulse-labeled with 14c-containing amino acids and homogenized, 14c-labeled membranes were obtained. in vitro incubations with the previously labeled membranes and udp-[3h]glc produced a trichloroacetic-acid-insoluble fraction having both isotopes. a double-labeled glucoprotein was isolated and characterized. it has a relative molecular mass of 28,000-30,000 and a carbohydrate content of 10%. the oligosaccharide chain is linked to the protein through an o-glycosi ... | 1987 | 3816793 |
| bovine mastitis caused by prototheca zopfii: a case study. | an outbreak of severe indurative mastitis in newly calved cows, from which prototheca zopfii was isolated, is described. the refractory nature of this type of mastitis and the ineffectiveness of the presently available intramammary preparations are highlighted. | 1985 | 4002543 |
| [differentiation of variants of prototheca zopfii krüger 1894]. | 1985 | 4051655 | |
| identification and characterization of mitochondrial translation products in various yeasts and in prototheca zopfii. | mitochondrial genomes of different eucaryotes are not all alike. we have examined mitochondrial translation products in a number of yeasts (candida krusei, hansenula saturnus, rhodotorula glutinis, rhodotorula rubra, torulopsis glabrata and saccharomyces cerevisiae) and in prototheca zopfii, a colorless alga, in order to determine whether certain proteins are invariably synthesized within mitochondria, how different these proteins are, and what additional proteins, if any, might be synthesized b ... | 1985 | 2836096 |
| prototheca 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 10(3) cells/ml) were recorded in five of the eight remaining cows. histological examination of udder tis ... | 1985 | 16031181 |
| β-glucan biosynthesis in synchronous cells of prototheca zopfii. | synchronous cultures of the colorless chlorophyte prototheca zopfii kruger were obtained by a shift-down of the basal medium plus addition of 1.5 mm ethylenediaminetetracetic acid for a 10-14-h period, followed by periodic dilutions with the basal medium. the cell cycle has a duration of 10-12 h at 25°c and an average of eight autospores are produced at the end of each cycle. the incorporation of [(14)c]glucose into β-glucans was determined in vivo. very high incorporation occurs between hours 3 ... | 1985 | 24241139 |
| investigation of the beta-lactamase activity of prototheca zopfii. | a total of 52 strains of prototheca zopfii were studied with a series of beta-lactam compounds in order to test possible existence of beta-lactamase capable of inactivating these compounds. the method used was based on the iodimetric technique. results showed the existence of beta-lactamase which worked in different degrees depending on the beta-lactam compounds. | 1984 | 6335827 |
| disseminated protothecosis in a dog. | a dog with forelimb lameness, bilateral retinal detachment, and hemorrhagic diarrhea, died. necropsy demonstrated multifocal lesions in the skeletal musculature, myocardium, liver, thyroid glands, kidneys, eyes, and brain. microscopically, the lesions contained numerous organisms and minimal cellular infiltrates. the morphologic and cultural characteristics of the organisms were similar to prototheca. the organisms in tissue sections reacted positively for prototheca zopfii, using an indirect fl ... | 1984 | 6501053 |
| natural and experimental bovine intramammary infection with prototheca zopfii. | a naturally occurring case of chronic mastitis caused by prototheca zopfii was detected in a dairy cow. the cow was observed for 12 weeks, and milk samples were cultured each week. milk production was decreased, and high numbers (greater than 10(3)/ml) of the organism were detected in the milk. six glands of 2 cows were inoculated with small numbers of p zopfii. all 3 cows were euthanatized, and at postmortem, a progressive pyogranulomatous inflammation was observed in all infected mammary gland ... | 1984 | 6711991 |
| ultrastructure of prototheca zopfii in bovine granulomatous mastitis. | mammary glands from cows with protothecal mastitis were examined by light and electron microscopy at 6, 13, 20, and greater than 180 days after infection. with increasing time, there were increases in severity of granulomatous inflammation, number of endospores and sporangia, and ratio of degenerate to intact algae. algae were found in macrophages but were not seen in neutrophils, epithelial cells, or myoepithelial cells. macrophages containing algae were markedly enlarged, chiefly from reduplic ... | 1984 | 6730224 |
| disseminated protothecosis causing acute blindness and deafness in a dog. | a 3-year-old collie bitch was euthanatized two weeks after the onset of blindness and deafness. the hearing deficit had been localized by clinical signs, brain stem auditory evoked responses, and impedance audiometry. protothecosis was diagnosed by cytologic and histologic examinations. the organism was identified as prototheca zopfii . organisms and granulomatous lesions were found in kidney, heart, liver, skeletal muscle, thyroid gland, colon, bronchial lymph node, brain, and cochlea. | 1984 | 6735845 |
| antimicrobial susceptibility of prototheca zopfii isolated from bovine intramammary infections. | in vitro antimicrobial susceptibility tests were carried out on 48 strains of prototheca zopfii, an achlorophyllous algae causing refractory mastitis in dairy cows; 27 antimicrobials were evaluated. all strains were susceptible to both myxin and nystatin. in addition, 22 strains were susceptible to amphotericin b, 21 to polymyxin b, and 18 to gentamicin. only 1 strain was susceptible to kanamycin. all strains were resistant to ampicillin, bacitracin, carbenicillin, cephalothin, chloramphenicol, ... | 1984 | 6742568 |
| simple new test for rapid differentiation of prototheca wickerhamii from prototheca zopfii. | a simple new test to differentiate prototheca wickerhamii from prototheca zopfii by determining susceptibility to clotrimazole is described. a 50-micrograms clotrimazole disk provides a rapid and reliable means of distinguishing p. wickerhamii from p. zopfii. | 1983 | 6630477 |
| [sensitivity of prototheca zopfii to antifungal, chemotherapeutic and sulfamide agents]. | 1983 | 6672941 | |
| prototheca zopfii krüger strain umk-13 growth on acetate or n-alkanes. | a new strain of prototheca zopfii krüger was grown on acetate or on pure n-alkanes. a maximum acetate-supported exponential growth of 12 divisions day occurred at ph 5 and 30 degrees c. at 25 degrees c, growth on n-alkanes was almost as fast, but no growth occurred at 30 degrees c. after 4 days at 25 degrees c, 34 to 45% of the n-alkanes had been removed, whereas at 21 degrees c and slower growth, utilization was twofold greater after 15 days. rates of growth and utilization increased markedly a ... | 1983 | 16346176 |
| canine protothecosis: review of the literature and report of an additional case. | a review of protothecosis in dogs revealed that this malady usually begins in the gastrointestinal tract and progresses to systemic involvement. clinical signs generally include bloody diarrhea or blood-stained feces as well as blindness, ataxia, and polyuria. histologically, myriads of protothecal organisms in different stages of development are found in the granulomatous lesions. two main species have been culturally identified: prototheca zopfii and p wickerhamii. in the absence of cultural s ... | 1982 | 6754671 |
| [prototheca zopfii colonizing the nail]. | 1981 | 7278940 | |
| the effect of amphotericin b on the ultrastructure of prototheca species. | prototheca zopfii and prototheca wickerhamii stains were exposed to subinhibitory concentrations of the antimycotic amphotericin b, and the effect of the treatment on their ultrastructure was assessed. the results revealed ultrastructural changes in the treated cells, expressed by swelling of mitochondria, degradation of cell organelles, accumulation of microbody like structures, lipid droplets and starch granules in the cytoplasm, and changes in the inner layer of the cell wall. | 1981 | 7322192 |
| disseminated protothecosis with central nervous system involvement in a dog. | a 4-year-old mixed-breed spayed bitch was euthanatized after 2 1/2 months of progressive neurologic disease. prototheca organisms were identified by histopathology, culture, and electron microscopy. specific fluorescent antibody procedures revealed two species--prototheca wickerhamii and prototheca zopfii. organisms and pyogranulomatous lesions were found in the brain, spinal cord, right eye, kidneys, and heart. | 1980 | 7380720 |
| experimental protothecosis in labortory animals. | attemps were made to produce protothecosis in laboratory animals by intratesticular, intraperitoneal, intravenous and subcutaneous inoculation of prototheca zopfii, p. wickerhamii and p stagnorta. only intratesticular injection successfully caused infection, and of the inoculated protothecae, only p. zopfii and p. wickerhamii were recovered in culture from testicular material. | 1980 | 7434134 |
| lipid carriers in the synthesis of high-mannose glycoproteins in algae. | particulate preparations from the chlorophyta prototheca zopfii catalyze the incorporation of mannose and n-acetylglucosamine into glycolipids. these had been characterized as lipid monophosphate mannose, lipid pyrophosphate n,n'-diacetylchitobiose and various lipid-linked oligosaccharides containing two n-acetylglucosamine residues plus a variable number of mannose residues. the lipid moiety has the properties expected for dolichyl phosphate. the oligosacchride-linked lipids serve as precursors ... | 1979 | 476152 |
| growth of prototheca isolates on n-hexadecane and mixed-hydrocarbon substrate. | prototheca zopfii, an achlorphyllous alga, was capable of using hydrocarbons as sole carbon and energy source. the ability of p. zopfii to use hydrocarbons did not correlate with source of isolation. seventy-five percent of the p. zopfii cultures recovered from sewage, plants, or animals utilized hydrocarbons. other prototheca species and p. zopfii that did not utilize hydrocarbons were isolated simultaneously from several sources with isolates that did use hydrocarbons. species type rather than ... | 1978 | 565616 |
| bovine protothecosis. a brief report of ten cases. | prototheca zopfii was isolated repeatedly from milk samples from ten cows (of a herd of 192 dairy cows) with reduced milk yield and indurated mammary glands. the strain was moderately sensitive to streptomycin, polymyxin and gentamycin, but resistant or relatively resistant to other antibiotics and antimycotics commonly used in clinical practice. an attempt to treat the infection with ethidium bromide, which was found effective in vitro, did not succeed. the number of prototheca excreted decreas ... | 1978 | 665244 |
| biosynthesis of dolichyl phosphate: characterization and site of synthesis in algae. | this is the first report not only on the presence of polyprenyl phosphates and their site of synthesis in algae, but also on the formation of their sugar derivatives in this system.a glucose acceptor lipid was isolated from the nonphotosynthetic alga prototheca zopfii. the lipid was acidic and resistant to mild acid and alkaline treatments. the glucosylated lipid was labile to mild acid hydrolysis and resistant to phenol treatment and catalytic hydrogenation, as dolichyl phosphate glucose is. th ... | 1978 | 16660269 |
| susceptibility of prototheca species to antifungal agents. | twenty isolates of prototheca filamenta, prototheca moriformis, prototheca stagnora, prototheca wickerhamii, and prototheca zopfii were tested for in vitro susceptibility to five commonly used antifungal agents: amphotericin b, 5-fluorocytosine, griseofulvin, miconazole, and nystatin. the results revealed resistance to griseofulvin of all the prototheca isolates tested and an inhibitory effect on p. filamenta by high 5-fluorocytosine concentrations (minimal inhibitory concentration [mic] = 12.5 ... | 1976 | 984758 |
| the oxidation of terminal d-galactofuranose residues of a galactan and a glycoprotein by a d-galactose oxidase preparation from dactylium dendroides. | a galactan, isolated from the unicellular organism prototheca zopfii, and a glycoprotein from a hyphal cell-wall fraction of the fungus pithomyces chartarum have been oxidised by a d-galactose oxidase preparation from dactylium dendroides. the oxidised polymers were subsequently reduced with sodium borotritide. the site of oxidation was identified as c-6 of non-reducing d-galactofuranosyl residues in both polymers. | 1976 | 986873 |
| degradation of petroleum by an alga, prototheca zopfii. | prototheca zopfii is an achlorophyllous alga which degrades oil. it has been found to degrade 10 and 40% of a motor oil and crude oil, respectively, when tested under appropriate conditions. degradation of the crude oil observed in this study compares well with the amount of degradation accomplished by bacteria. p. zopfii was found to degrade a greater percentage of the aromatic hydrocarbons in motor oil than of the saturated hydrocarbons and a greater percentage of saturated hydrocarbons in cru ... | 1975 | 1147621 |
| effect of growth rate on the macromolecular composition of prototheca zopfii, a colorless alga which divides by multiple fission. | prototheca zopfii, a eukaryote that divides by multiple fission, was investigated to determine how growth rate controls daughter cell number. the macromolecular composition, cell size, and number of nuclei per cell were determined in cultures during balanced growth in various media. cellular mass, ribonucleic acid (rna), deoxyribonucleic acid (dna), carbohydrate, and nuclear number increased as positive linear functions of growth rate, whereas nuclear ploidy remained constant with a value of 0.0 ... | 1973 | 4120065 |
| the molecular structures of a glucan and a galactan synthesised by prototheca zopfii. | 1973 | 4356400 | |
| control of daughter-cell number variation in multiple fission: genetic versus environmental determinants in prototheca. | prototheca zopfii has been developed as an experimental system for studying the control of cytokinesis and daughter-cell number variation in multiple fission. although mean daughter-cell number increases linearly with growth rate, and this dependency is genetically controlled, pedigree analysis shows that daughter-cell number variation is not under direct genetic control. in a population growing in steady-state balanced growth, each cell has a given probability of dividing into 2, 4, 8 16, or 32 ... | 1972 | 4506103 |
| presence of two sets of ribosome-specific transfer factors in the cell-free extracts from the non-photosynthetic alga prototheca zopfii. | 1970 | 4907269 | |
| the cytochromes of prototheca zopfii. | the respiratory pigments of prototheca zopfii include seven cytochromes: two c-type cytochromes, a soluble c(549) and a membrane bound c(551); three b-type cytochromes, b(555), b(559) and b(564); and cytochromes a and a(3). cytochromes a and a(3) could be resolved spectrally in the alpha-band region by reducing the cells in the presence of methanol and cyanide. methanol shifted the absorption maximum of cytochrome a from 598 to 603 nanometers and permitted dithionite (or substrate) to reduce the ... | 1970 | 16657381 |
| inhibition of respiration in prototheca zopfii by light. | irradiation of cells of prototheca zopfii with blue light inhibited the respiratory capacity of the cells. the inhibition of respiration was correlated with a photodestruction of cytochrome c(551), cytochrome b(559), and cytochrome a(3). cytochrome c(549), cytochrome b(555), and cytochrome b(564) were unaffected by the irradiation treatment. the alpha-band of reduced cytochrome a was shifted from 599 to 603 nm by irradiation, an effect similar to that observed when methanol was added to nonirrad ... | 1970 | 16657382 |
| cytochrome a3: destruction by light. | spectroscopic measurements on cultures of prototheca zopfii irradiated with blue light revealed that inhibition of respiration was accompanied by destruction of cytochrome a(3). one of the three b-type cytochromes and one of the two c-type cytochromes of this organism were also affected. cytochrome oxidase of yeast (not resolved into the a and a(3) components) and cytochrome a(3) of beef-heart mitochondria were also destroyed by blue light. | 1969 | 4309889 |
| the cell wall of prototheca zopfii. | 1968 | 5652075 | |
| the isolation of mitochondria from the colourless alga prototheca zopfii. | 1967 | 4290159 | |
| the regulation of propionate oxidation in prototheca zopfii. | 1. whole cell suspensions of prototheca zopfii grown on propionate oxidize propionate, acrylate, malonic semialdehyde and acetate immediately, whereas acetate-grown cells only oxidize acrylate or propionate rapidly after a lag of 20-30min. this adaptation to propionate is slowed down by 8-azaguanine or p-fluorophenylalanine, and is not influenced by adding an ammonium salt or an amino acid mixture. 2. the adaptation involves induction of the enzymes of beta-oxidation of propionate. 3. a small pr ... | 1967 | 6048804 |
| influence of the nitrogen source on the adenine reversal of 3-amino-1,2,4-triazole inhibition of prototheca zopfii growth. | 1967 | 6064046 | |
| effect of 3-amino-1,2,4-triazole on histidine metabolism in algae. | growth of chlorella vulgaris and prototheca zopfii is inhibited by treatment with 3-amino-1,2,4-triazole. growth of these 2 algae in the presence of amino triazole is accompanied by the accumulation in the culture media of the dephosphorylated histidine precursor, imidazoleglycerol. the addition of histidine to the culture media in the presence of amino triazole restored the normal growth rates of these organisms and reduced the accumulation of imidazoleglycerol. these data suggest that amino tr ... | 1966 | 5932405 |
| the inhibitory effect of light on growth of prototheca zopfii kruger. | 1966 | 5961109 | |
| level of vitamin b12 in propionate-grown prototheca zopfii. | 1966 | 5962129 | |
| the purification and properties of malonic semialdehyde oxidative decarboxylase from prototheca zopfii. | 1. an enzyme, which in the presence of nad(+) and coa oxidizes malonic semialdehyde to acetyl-coa, has been purified from an extract of the colourless alga prototheca zopfii. 2. the purified enzyme has optimum ph7.5, is specific for nad(+) and requires a thiol compound for maximum activity. 3. the enzyme is inhibited by arsenite, n-ethylmaleimide and urea. 4. the results are discussed in relation to those obtained by other workers with a similar bacterial enzyme, and a possible reaction sequence ... | 1965 | 4285894 |
| respiratory control in mitochondria isolated from the colourless alga prototheca zopfii. | 1965 | 5866392 | |
| the assimilation of acetate and propionate by prototheca zopfi. | 1. the tricarboxylic acid and glyoxylate cycles are of major importance in the assimilation of acetate and propionate by prototheca zopfii. the pattern of assimilation of [2-(14)c]acetate and [2-(14)c]propionate by whole cells growing with their respective substrates is similar except that, with propionate, beta-hydroxypropionate is the first labelled intermediate detected. 2. carbon dioxide fixation is of little quantitative importance for the growth of this organism with propionate. 3. the yie ... | 1965 | 16749100 |
| the metabolism of acetate in the colourless alga, prototheca zopfii. | 1964 | 5834509 | |
| the metabolism of propionate in the colourless alga, prototheca zopfii. | 1964 | 4284461 | |
| carbohydrate metabolism of prototheca zopfii. i. enzymes of the glycolytic and hexose monophosphate pathways. | 1962 | 13879522 | |
| carbon dioxide fixation by the achloric alga prototheca zopfii. | 1961 | 13879523 | |
| nature of the growth factor for the colorless alga prototheca zopfii. | 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 ... | 1945 | 19873421 |
| studies 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 certain compounds. the phosphoric ester of thiamin is known to be the prosthetic group of carboxylase. the ... | 1945 | 19873422 |