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141.
142.
Corecovery of lipids and fermentable sugars from Rhodosporidium toruloides using ionic liquid cosolvents: Application of recycle to batch fermentation
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This work evaluates the ability of an ionic liquid‐methanol cosolvent system to extract lipids and recycle fermentable sugars recovered from oil‐bearing Rhodosporidium toruloides grown in batch culture on defined media using glucose and xylose as carbon sources. Growth on the recycled mixed carbon substrate was successful with glucose consumed before xylose and overall cell mass to lipid yields (YP/X) between 57% and 61% (w/w relative to whole dried cell mass) achieved. Enzymatic hydrolysis of the delipified carbohydrate fraction recovered approximately 9%–11% (w/w) of the whole dried cell mass as fermentable sugars, which were successfully recycled as carbon sources without further purification. In total, up to 70% (w/w) of the whole dried cell mass was recovered as lipids and fermentable sugars and the substrate to lipid yields (YP/S) was increased from 0.12 to 0.16 g lipid/g carbohydrate consumed, highlighting the promise of this approach to process lipid bearing cell biomass. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:1239–1242, 2014 相似文献
143.
Adaptions of the polymerase chain reaction were used to isolate cDNA sequences encoding the Major histocompatibility complex(Mhc) class II A gene(s) of the striped bass (Morone saxatilis). Four complete Mhc class II A genes were cloned and sequenced from a specimen originating in the Roanoke River, North Carolina, and another three A genes from a specimen originating from the Santee-Cooper Reservoir, South Carolina, identifying a total of seven unique sequences. The sequence suggests the presence of at least two Mhc class II A loci. The extensive sequence variability observed between the seven different Mhc class II clones was concentrated in the 1 encoding domain. The encoded 2, transmembrane, and cytoplasmic regions of all seven striped genes correlated well with those of known vertebrate Mhc class II proteins. Overall, the striped bass sequences showed greatest similarity to the Mhc class II A genes of the zebrafish. Southern blot analysis demonstrated extensive polymorphism in the Mhc class II A genes in members of a Roanoke river-caught population of striped bass versus a lesser degree of polymorphism in an aquacultured Santee-Cooper population of striped bass.The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the accession numbers (Mosa-A-S5) L35062, (Mosa-A-S8) L35066, (Mosa-A-R7) L35067, and (Mosa-A-S7) L35072 L35066, (Mossa-A-R7) L35067, and (Mosa-A-S7) L35072 相似文献
144.
Two distinct origins of a common BRCA1 mutation in breast-ovarian cancer families: a genetic study of 15 185delAG-mutation kindreds. 总被引:8,自引:3,他引:5
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D. B. Berman J. Wagner-Costalas D. C. Schultz H. T. Lynch M. Daly A. K. Godwin 《American journal of human genetics》1996,58(6):1166-1176
We screened 163 women from breast-ovarian cancer-prone families, as well as 178 individuals affected with breast and/or ovarian cancer but unselected for family history, for germ-line mutations in exon 2 of BRCA1, by SSCP analysis and direct sequencing. A total of 25 mutations were detected. Thirteen of 64 Jewish Ashkenazi women and 2 non-Jewish individuals were found to possess the 185delAG mutation. Haplotype data for all 15 individuals, with markers intragenic to BRCA1, suggest that the Jewish Ashkenazi individuals share a common ancestry that is distinct from the lineage shared by the other two women. These data provide the first evidence of two distinct lines of transmission for the 185delAG mutation, only one of which has its origins in the Jewish Ashkenazi population. Our screening also uncovered 10 affected individuals with an 11-bp deletion at nucleotide 188 of BRCA1 (188del11), 4 of whom are Ashkenazi Jews. This is only the third reported mutation detected within the Jewish Ashkenazi population and may represent the second most common alteration in BRCA1 found in Ashkenazi Jews in the United States. The observed overrepresentation of specific mutations within a subgroup of the general population may eventually contribute to the development of inexpensive and routine tests for BRCA1 mutations, as well as to the elucidation of other contributory factors (e.g., diet, environment, and chemical exposures) that may play a key role in cancer initiation and development. The implications of the mutational data, as well as the role that founder effect, demographic history, and penetrance play in the resulting observed phenomena, are discussed. 相似文献
145.
The ribosomal DNAs from Ch. thummi piger and Ch. th. thummi were cloned and analysed by a variety of restriction endonucleases. Comparison of rDNA clones from the two subspecies revealed a considerable length difference: the length of the analysed rDNA cistrons is approximately 9.0 kb for Ch. th. piger and approximately 14.5 kb for Ch. th. thummi. The nearly 5 kb additional DNA in Ch. th. thummi is clearly located within the non-transcribed spacer region, and consists of AT-rich, reptitive DNA elements. These elements with a basic repeat length of approximately 120 bp, are arranged tandemly in stretches of up to about 50 identical copies, which are characterized by a cleavage site for ClaI restriction endonuclease. They are found only in the Ch. th. thummi rDNA clones and not in the Ch. th. piger clones. Southern hybridizations between cloned ribosomal DNA and centromeric highly repetitive DNA have shown that the ribosomal repetitive Cla-elements are closely related to a highly repetitive DNA sequence family, which is present in various chromosomal sites particularly the centromeres. Sequence analysis has revealed more than 90% homology between the ribosomal Cla-elements and the centromeric Cla-elements. — Since it is clear from cytological investigations that Ch. th. piger with the small rDNA repeating unit is the phylogenetically older subspecies, we postulate a transposition of Cla-elements into the nucleolar DNA during the evolution of Ch. th. thummi. 相似文献
146.
Esther N. Mwangi Olusegun O. Dipeolu Robin M. Newson Godwin P. Kaaya Shwagi M. Hassan 《Biocontrol Science and Technology》1991,1(3):147-156
Research conducted on natural enemies of ticks, namely predators, parasitoids and pathogens, is reviewed. Predators include ants, birds, rodents, lizards, shrews, spiders and domestic chickens. All the known parasitoids are hymenopteran wasps belonging to the genera Ixodiphagus and Hunterellus. The work so far done on bacteria, fungi, viruses and rickettsiae which are pathogenic to ticks is reviewed, both with regard to experimental infections and natural infections. The possibilities of using natural enemies as biological control agents of ticks are discussed. 相似文献
147.
The fate of selenium, given as Na2(75)SeO3, or [75Se]selenomethionine, and of [35S]methionine administered intravenously to ewes and lambs, has been examined. The main intention was to follow the incorporation of selenium into protein in a number of tissues, including liver and kidney, and to measure the extent of that incorporation of selenoamino acid, particularly with respect to the administration of selenite. The ewes chosen were lactating ewes with lambs at foot, and the lambs were animals which had been weaned on to fodder low in selenium and were recovering from white muscle disease with selenium therapy. These two experimental situations were chosen as they offered conditions under which selenium incorporation might be considered to be maximal. Entry of isotope into milk was rapid and was greater when 75Se was given as the selenoamino acid than as selenite. In both ewes and lambs greater amounts of activity, derived from selenite, were bound to plasma proteins than to the proteins of milk. This was particularly evident in samples taken some hours after administration. This ability of the plasma to bind selenium was demonstrated by alkaline dialysis. Small, though significant amounts of selenium, derived from Na2(75)SeO3, were incorporated as selenoamino acids into the proteins of liver, kidney and pancreas, as well as into the proteins of milk and plasma. In ewes, both selenomethionine and selenocystine were identified chromatographically in enzyme digests of defatted liver and kidney. Some differences occurred in the distribution of labelled compounds in organs from lactating ewes and recovering lambs. The incorporation of selenium into protein is discussed briefly in relation to the recent findings of an association between selenium and the enzyme glutathione peroxidase. 相似文献
148.
149.
In the laboratory, pupae ofLymantria dispar (L.) parasitized byBlepharipa pratensis (Meigen) were exposed to femaleBrachymeria intermedia (Nees) to determine whether the females would attack such pupae, and if they did, what was the fate ofB. pratensis. B. intermedia did attack parasitized pupae, andB. pratensis survived these attacks about 78% of the time. However, in those cases whereB. pratensis appears not to have survived, butB. intermedia did survive, the evidence suggests that the host pupae had not been parasitized byB. pratensis at the time of attack. Field observations also support the conclusion thatB. intermedia is not a significant mortality factor ofB. pratensis. 相似文献
150.