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111.
The cDNA cloning and molecular evolution of reptile and pigeon lactate dehydrogenase isozymes 总被引:1,自引:0,他引:1
The cDNAs encoding lactate dehydrogenase isozymes LDH-A (muscle) and LDH-B
(heart) from alligator and turtle and LDH-A, LDH-B, and LDH-C (testis) from
pigeon were cloned and sequenced. The evolutionary relationships among
vertebrate LDH isozymes were analyzed. Contrary to the traditional belief
that the turtle lineage branched off before the divergence between the
lizard/alligator and bird lineages, the turtle lineage was found to be
clustered with either the alligator lineage or the alligator-bird clade,
while the lizard lineage was found to have branched off before the
divergence between the alligator/turtle and bird lineages. The pigeon
testicular LDH-C isozyme was evidently duplicated from LDH-B (heart), so it
is not orthologous to the mammalian testicular LDH-C isozymes.
相似文献
112.
J. A. Gracia-Garza B. A. Bailey T. C. Paulitz R. D. Lumsden R. D. Releder D. P. Roberts 《Biocontrol Science and Technology》1997,7(3):401-414
Damaged sclerotia of Sclerotinia sclerotiorum buried in soil infested with Trichoderma hamatum isolate TMCS - 3 were degraded rapidly when the medulla of sclerotia was com pletely exposed by the feeding activity of larvae of the fungus gnat Bradysia coprophila. These heavily damaged sclerotia also enhanced , in vitro, the growth of TMCS - 3 . Growth of TMCS - 3 in liquid culture was studied using different carbon sources as substrates , including sclerotia of S. sclerotiorum. Significantly more biomass of TMCS - 3 was recovered using sclerotia as a substrate compared to other carbon sources tested . Exudates from sclerotia whose melanized rinds had been completely removed by feeding larvae accelerated the germination of conidia of TMCS - 3 . Concentrations of amino acids , carbohydrates and proteins in the sclerotial exudates were not increased as damage to sclerotia was increased . Exudation of electrolytes was higher in undamaged than damaged sclerotia . Glucanase activity of TMCS - 3 was slightly increased when the fungus was exposed to damaged sclerotia . However , chitinase activity was not increased by damaging the sclerotia . Larval damage altered the sclerotia not only physically but also chemically , thereby enhancing the activity of the fungus T. hamatum. 相似文献
113.
114.
M A Lumsden R W Kelly A A Templeton P F Van Look I A Swanston D T Baird 《Journal of reproduction and fertility》1986,77(1):119-124
The concentrations of prostaglandins F-2 alpha, E, D-2 and 13,14-dihydro-15-keto PGE were measured in follicular fluid collected from women undergoing routine laparoscopy following induction of follicular development with clomiphene and hCG. Laparoscopy was performed before, or at 12, 24 or 36 h after administration of hCG. Prostaglandins were measured as the methyloxime derivative by radioimmunoassay. Peaks in PGE and PGF-2 alpha concentration occurred at 12 and 36 h with a significant nadir at 24 h, whereas PGD-2 production was very low at 36 h. The concentration of PGF-2 alpha rose significantly between 0 and 36 h and was greatest in follicles yielding oocytes, suggesting a possible role for this prostaglandin in the mechanism of follicle rupture. 相似文献
115.
Information concerning habitat, body size, reproductive status, and diet was recorded from 348 greater galagos, captured at
six different localities in Tanzania and southern Africa between 1953 and 1955. The localities extended from Pemba Island
in the north to Chikwawa, Malawi, in the south and varied broadly in the same order in degree of climatic aridity— from well-watered
clove and coconut plantations to seasonally very dry woodland. Animals from the three northern localities fell within the
geographic range of Galago garnettii,while the rest were assumed to be G. crassicaudatus.Statistical analysis of body size parameters confirmed this allocation. Data on fetal occurrence, vaginal and labial condition,
and lactation indicate a restricted breeding season for both species, with peak proportions in estrus in August in G. garnettiiand in May-July in G. crassicaudatus.Gut content data indicate a variety of foods, with a preponderance in the northern localities of soft fruit such as mango,
pawpaw, and coconut pulp; gum was a major carbohydrate source in the southernmost localities. Contrary to expectations, tooth
damage, in the form of both loss and breakage, was much more prevalent in G. garnettiithan in G. crassicaudatus.The teeth most commonly lost were the upper incisors— perhaps because of the high acid and sugar content of a frugivorous
diet. The high incidence of breakage of the lower incisors and upper canines indicates the inclusion of hard-shelled food
sources in the diet of G. garnettii. 相似文献
116.
A well-characterized crude peroxisomal fraction from brown adipose tissue was used to compare peroxisomal beta-oxidation with beta-oxidation in isolated mitochondria. The apparent Km and chain-length specificity for peroxisomal (acyl-CoA) and mitochondrial (acyl-carnitine) beta-oxidation were determined with saturated C4-C22 fatty acyls and some unsaturated fatty acyls. Peroxisomes showed the lowest Km for medium-chain (9:0-10:0) and mono-unsaturated long-chain (16:1-22:1) fatty acids, and highest oxidation rates with lauroyl-CoA (12:0). Mitochondria showed the lowest Km for long-chain fatty acids (16:0-18:0) and highest oxidation rates with 12:0-16:0 and with 18:2. These in vitro results offer an explanation of previous results obtained in situ by Foerster et al. (Foerster, E.-C., F?hrenkemper, T., Rabo, U., Graf, P. and Sies, H. (1981) Biochem. J. 196, 705-712) and indicate a role for peroxisomes in degradation of medium-chain and mono-unsaturated long-chain fatty acids. It is concluded that no mechanism, other than relative preferences, needs to be suggested for channelling of fatty acids between the two subcellular organelles. 相似文献
117.
Jason W. Bennett Anjali Yadava Donna Tosh Jetsumon Sattabongkot Jack Komisar Lisa A. Ware William F. McCarthy Jessica J. Cowden Jason Regules Michele D. Spring Kristopher Paolino Joshua D. Hartzell James F. Cummings Thomas L. Richie Joanne Lumsden Edwin Kamau Jittawadee Murphy Cynthia Lee Falgunee Parekh Ashley Birkett Joe Cohen W. Ripley Ballou Mark E. Polhemus Yannick F. Vanloubbeeck Johan Vekemans Christian F. Ockenhouse 《PLoS neglected tropical diseases》2016,10(2)
Background
A vaccine to prevent infection and disease caused by Plasmodium vivax is needed both to reduce the morbidity caused by this parasite and as a key component in efforts to eradicate malaria worldwide. Vivax malaria protein 1 (VMP001), a novel chimeric protein that incorporates the amino- and carboxy- terminal regions of the circumsporozoite protein (CSP) and a truncated repeat region that contains repeat sequences from both the VK210 (type 1) and the VK247 (type 2) parasites, was developed as a vaccine candidate for global use.Methods
We conducted a first-in-human Phase 1 dose escalation vaccine study with controlled human malaria infection (CHMI) of VMP001 formulated in the GSK Adjuvant System AS01B. A total of 30 volunteers divided into 3 groups (10 per group) were given 3 intramuscular injections of 15μg, 30μg, or 60μg respectively of VMP001, all formulated in 500μL of AS01B at each immunization. All vaccinated volunteers participated in a P. vivax CHMI 14 days following the third immunization. Six non-vaccinated subjects served as infectivity controls.Results
The vaccine was shown to be well tolerated and immunogenic. All volunteers generated robust humoral and cellular immune responses to the vaccine antigen. Vaccination did not induce sterile protection; however, a small but significant delay in time to parasitemia was seen in 59% of vaccinated subjects compared to the control group. An association was identified between levels of anti-type 1 repeat antibodies and prepatent period.Significance
This trial was the first to assess the efficacy of a P. vivax CSP vaccine candidate by CHMI. The association of type 1 repeat-specific antibody responses with delay in the prepatency period suggests that augmenting the immune responses to this domain may improve strain-specific vaccine efficacy. The availability of a P. vivax CHMI model will accelerate the process of P. vivax vaccine development, allowing better selection of candidate vaccines for advancement to field trials. 相似文献118.
Thomas Lumsden Amber A. Bentley William Beutler Arnab Ghosh Oleksandr Galkin Anton A. Komar 《Nucleic acids research》2010,38(4):1261-1272
Ribosomal protein (rp)S5 belongs to the family of the highly conserved rp’s that contains rpS7 from prokaryotes and rpS5 from eukaryotes. Alignment of rpS5/rpS7 from metazoans (Homo sapiens), fungi (Saccharomyces cerevisiae) and bacteria (Escherichia coli) shows that the proteins contain a conserved central/C-terminal core region and possess variable N-terminal regions. Yeast rpS5 is 69 amino acids (aa) longer than the E. coli rpS7 protein; and human rpS5 is 48 aa longer than the rpS7, respectively. To investigate the function of the yeast rpS5 and in particular the role of its N-terminal region, we obtained and characterized yeast strains in which the wild-type yeast rpS5 was replaced by its truncated variants, lacking 13, 24, 30 and 46 N-terminal amino acids, respectively. All mutant yeast strains were viable and displayed only moderately reduced growth rates, with the exception of the strain lacking 46 N-terminal amino acids, which had a doubling time of about 3 h. Biochemical analysis of the mutant yeast strains suggests that the N-terminal part of the eukaryotic and, in particular, yeast rpS5 may impact the ability of 40S subunits to function properly in translation and affect the efficiency of initiation, specifically the recruitment of initiation factors eIF3 and eIF2. 相似文献
119.
120.