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1.
Definitions are proposed for the independent and joint contributions that the chemical groups A and B make to the free energy of association of the ligand A?B with a receptor. The definitions are independent of the choice of the standard state and are consistent with the basic thermodynamic cycle relating the association of the ligands A?B, A?Y and X?B to the receptor Rappaport 1976. The basic idea is the use of the excess free energy of association of the ligand A?Y over the free energy of association of the reference ligand X?Y as the measure of the “independent” contribution of the group A to the binding. This definition allows the free energy of association of the ligand A?B to be written as the sum of the independent contributions of the groups A and B, their joint contribution, and an invariant free energy of association of the reference ligand with any receptor. With the appropriate definition of the receptor-reference ligand complex, water can be chosen as the reference ligand. Using ΔG(A?OH)?AG(HOH), ΔG(H?B?H)?ΔG(HOH) and ΔG(HO?C)?ΔG(HOH) as the definitions of the “independent” contributions of the chemical groups A, B and C to the binding of the ligand A?B?C, the joint contribution of the groups A and C to the binding is ΔG(A?B?C) ? ΔG(A?B?H) ? ΔG(H-B-C) + ΔG(H?B?H). 相似文献
2.
The Australian species of the genus Trigonopterus Fauvel are revised. Eight previously recognized species are redescribed and 24 additional new species are described: Trigonopterus
allaetus Riedel, sp. n., Trigonopterus
athertonensis Riedel, sp. n., Trigonopterus
australinasutus Riedel, sp. n., Trigonopterus
australis Riedel, sp. n., Trigonopterus
bisignatus Riedel, sp. n., Trigonopterus
bisinuatus Riedel, sp. n., Trigonopterus
boolbunensis Riedel, sp. n., Trigonopterus
cooktownensis Riedel, sp. n., Trigonopterus
daintreensis Riedel, sp. n., Trigonopterus
deplanatus Riedel, sp. n., Trigonopterus
finniganensis Riedel, sp. n., Trigonopterus
fraterculus Riedel, sp. n., Trigonopterus
garradungensis Riedel, sp. n., Trigonopterus
hasenpuschi Riedel, sp. n., Trigonopterus
hartleyensis Riedel, sp. n., Trigonopterus
kurandensis Riedel, sp. n., Trigonopterus
lewisensis Riedel, sp. n., Trigonopterus
montanus Riedel, sp. n., Trigonopterus
monteithi Riedel, sp. n., Trigonopterus
mossmanensis Riedel, sp. n., Trigonopterus
oberprieleri Riedel, sp. n., Trigonopterus
robertsi Riedel, sp. n., Trigonopterus
terraereginae Riedel, sp. n., Trigonopterus
yorkensis Riedel, sp. n.. All new species are authored by the taxonomist-in-charge, Alexander Riedel. Lectotypes are designated for the following names: Idotasia
aequalis Pascoe, Idotasia
albidosparsa Lea, Idotasia
evanida Pascoe, Idotasia
laeta Lea, Idotasia
rostralis Lea, Idotasia
sculptirostris Lea, Idotasia
squamosa Lea. A new combination of the name Idotasia
striatipennis Lea is proposed: Trigonopterus
striatipennis (Lea), comb. n.. A key to the species is provided. Australian Trigonopterus occur in coastal Queensland, narrowly crossing into New South Wales. The southern parts of the range are inhabited by species found on foliage. A rich fauna of 19 edaphic species inhabiting the leaf litter of tropical forests is reported for the first time from the Australian Wet Tropics. 相似文献
3.
Alexander A. Khaustov 《ZooKeys》2014,(454):13-28
Five species of myrmecophilous microdispid mites (Acari: Microdispidae) are recorded from Western Siberia, Russia. Unguidispus
lasii Kurosa, 1979, Unguidispus
japonicus Kurosa, 1979, Caesarodispus
minutus (Sevastianov, 1981), and Caesarodispus
samsinaki (Mahunka, 1967), comb. n. are reported from Russia for the first time. Unguidispus
polyctenus (Sevastianov, 1969) and Caesarodispus
samsinaki are redescribed. The keys to species of the genera Unguidispus Mahunka, 1970 and Caesarodispus Mahunka, 1977 are provided. 相似文献
4.
The subgenus Orthoscymnus Canepari, 1997 of Scymnus Kugelann, 1794 is herein revised. Seven species of the Orthoscymnus fauna are recognized, of which four species, Scymnus (Orthoscymnus) jilongicus
sp. n., Scymnus (Orthoscymnus) paradoxus
sp. n., Scymnus (Orthoscymnus) crispatus
sp. n. and Scymnus (Orthoscymnus) duomaculatus
sp. n., are described as new to science. Scymnus (Orthoscymnus) rhododendri Canepari is recorded from China for the first time. Scymnus (Pullus) robustibasalis Yu is transferred to the subgenus Orthoscymnus (comb. n.). All species are diagnosed, described and illustrated, and distributions are provided for each species. A key to the species is included. 相似文献
5.
A list of the 356 species of Cecidomyiidae (Diptera) recorded from Finland is presented, which comprises 6 Lestremiinae, 156 Micromyinae, 16 Winnertziinae, 69 Porricondylinae, and 109 Cecidomyiinae. The faunistic knowledge of Finnish Winnertziinae, Porricondylinae and Cecidomyiinae is regarded as particularly poor. Based on species numbers known from other countries in Europe, a conservative estimate is 700–800 species of Cecidomyiidae actually occurring in Finland. 相似文献
6.
Jari Ilmonen 《ZooKeys》2014,(441):91-95
A checklist of the family Simuliidae (Diptera) is provided for Finland and recognizes 56 species. One new record has been added (Simulium
latipes) and one name sunken in synonymy (Simulium
carpathicum). Furthermore, Simulium
tsheburovae is treated as a doubtful record. 相似文献
7.
The present checklist includes data on the species composition, geographic distribution and feeding preferences of thrips species in Bulgaria. In total, 155 species in 48 genera are listed. Of these, 125 species belong to suborder Terebrantia and include 103 species of 33 genera in family Thripidae, 14 species of two genera in Aeolothripidae, seven species of two genera in Melanthripidae and one species in Fauriellidae. In suborder Tubulifera, 30 species of 10 genera in the single family Phlaeothripidae are listed. Of the 155 Bulgarian thrips species, 87.7% are phytophagous, 4.5% are obligate predators, 5.8% are mycophagous and 1.9% are with unknown feeding preferences. Fourteen pest species are listed for Bulgaria, of which Frankliniella
occidentalis, Thrips
tabaci and Haplothrips
tritici are of economic importance. The list provides detailed information on the horizontal and vertical distribution of Thysanoptera in 5 regions and 45 subregions of Bulgaria. The present paper also includes an evaluation of the biodiversity of Thysanoptera and the extent to which each region of the country has been studied. 相似文献
8.
Yousif Ali Dolatrai M. Vyas Robert C. Nabinger Walter A. Szarek 《Carbohydrate research》1982,104(2):183-193
Nucleophilic Michael-type additions to aldohexofuranoid 3-C-methylene derivatives, namely, 3-deoxy-1,2:5,6-di-O-isopropylidene-3-C-nitromethylene-α-d-ribo-hexofuranose and 3-C-[cyano(ethoxycarbonyl)methylene]-3-deoxy-1,2:5,6-di-O-isopropylidene-α-d-ribo-hexofuranose employing phase-transfer catalysis, afforded novel gem-di-C-substituted sugars. The conversion of 3-deoxy-1,2:5,6-di-O-isopropylidene-3-C-methyl-3-C-nitromethyl-α-d-allo-hexofuranose into a 3-C-hydroxymethyl-3-C-methyl derivative with titanium trichloride, and that of the nitromethyl groups of 3-deoxy-1,2:5,6-di-O-isopropylidene-3,3-di-C-nitromethyl-α-d-ribo-hexofuranose, and 3-deoxy-1,2:5,6-di-O-isopropylidene-3-C-methyl-3-C-nitromethyl- and -3-C-nitromethyl-α-d-allo-hexofuranose into cyano groups with phosphorus trichloride in pyridine is also described. 相似文献
9.
Jakeline Renata Marçon Delamuta Pâmela Menna Renan Augusto Ribeiro Mariangela Hungria 《Systematic and applied microbiology》2017,40(5):254-265
Bradyrhizobium comprises most tropical symbiotic nitrogen-fixing strains, but the correlation between symbiotic and core genes with host specificity is still unclear. In this study, the phylogenies of the nodY/K and nifH genes of 45 Bradyrhizobium strains isolated from legumes of economic and environmental importance in Brazil (Arachis hypogaea, Acacia auriculiformis, Glycine max, Lespedeza striata, Lupinus albus, Stylosanthes sp. and Vigna unguiculata) were compared to 16S rRNA gene phylogeny and genetic diversity by rep-PCR. In the 16S rRNA tree, strains were distributed into two superclades—B. japonicum and B. elkanii—with several strains being very similar within each clade. The rep-PCR analysis also revealed high intra-species diversity. Clustering of strains in the nodY/K and nifH trees was identical: 39 strains isolated from soybean grouped with Bradyrhizobium type species symbionts of soybean, whereas five others occupied isolated positions. Only one strain isolated from Stylosanthes sp. showed similar nodY/K and nifH sequences to soybean strains, and it also nodulated soybean. Twenty-one representative strains of the 16S rRNA phylogram were selected and taxonomically classified using a concatenated glnII-recA phylogeny; nodC sequences were also compared and revealed the same clusters as observed in the nodY/K and nifH phylograms. The analyses of symbiotic genes indicated that a large group of strains from the B. elkanii superclade comprised the novel symbiovar sojae, whereas for another group, including B. pachyrhizi, the symbiovar pachyrhizi could be proposed. Other potential new symbiovars were also detected. The co-evolution hypotheses is discussed and it is suggested that nodY/K analysis would be useful for investigating the symbiotic diversity of the genus Bradyrhizobium. 相似文献
10.
In this study, the spatial distribution of brood-bearing females of five species of limnetic cladocerans (Daphnia cucullata, D. longispina, Bosmina coregoni, B. longirostris, Diaphanosoma brachyurum) in the deep mesotrophic lake in relation to the predation pressure of planktivorous fish (roach Rutilus rutilus, perch Perca fluviatilis, catfish Ictalurus nebulosus, white fish Coregonus albula, bleak Alburnus alburnus), and planktonic invertebrates (cyclopoids Mesocyclops leuckartii, Thermocyclops oithonoides, T. crassus, and cladoceran Leptodora kindtii) as well as some environmental variables was estimated. Most cladocerans showed apparent differences in horizontal distribution (ANOVA F = 0.2–0.45, P < 0.05) in the littoral zone and lack of such differences in the pelagic zone (F = 0.07–0.13, P > 0.05). Vertical distribution of most species, in turn, showed a clear pattern in the pelagic zone (F = 0.31–0.39, P < 0.05) and less regularities in the littoral zone (F = 0.15–029, P > 0.05). The differences in spatial distribution of non-predated and predated species suggest that predation pressure, but not predatory type, was an important factor structuring their distribution. Other factors that affected their distribution were conductivity, dissolved oxygen, TOC and macrophyte biomass; however, most of those variables better explained the distribution of brood-bearing cladocerans in the vertical than horizontal aspect. 相似文献
11.
12.
13.
《Carbohydrate research》1986,148(2):235-247
The photo-oxygenation of ethyl 2-methyl-5-(1,2,3,4-tetra-O-acetyl-d-lyxo-tetritol-1-yl)-3-furoate, ethyl 2-methyl-5-(1,2,3,4-tetra-O-acetyl-d-arabino-tetritol-1-yl)-3-furoate, 3-acetyl-2-methyl-5-(1,2,3,4-tetra-O-acetyl-d-arabino-tetritol-1-yl)furan, and ethyl 5-(1,4-di-O-acetyl-2,3-O-isopropylidene-d-lyxo-tetritol-1-yl)-2-methyl-3-furoate yielded the corresponding 1,4-endo-peroxides (3a–3d as pairs of diastereomers). Each diastereomer of the pairs 3a and 3d was isolated by fractional crystallisation. The rearrangement of the endo-peroxides at room temperature, by dissolution in CDCl3, yielded the corresponding diepoxides and monoepoxides. The reduction of 3a–3d with methyl sulphide yielded the corresponding γ-diketones, ethyl (E)-2-C-acetyl-5,6,7,8-tetra-O-acetyl-2,3-dideoxy-d-lyxo-oct-2-en-4-ulosonate, ethyl (E)-2-C-acetyl-5,6,7,8-tetra-O-acetyl-2,3-dideoxy-d-arabino-oct-2-en-4-ulosonate, 3-C-acetyl-6,7,8,9-tetra-O-acetyl-1,3,4-trideoxy-d-arabino-non-3-eno-2,5-diulose, and ethyl (E)-2-C-acetyl-5,8-di-O-acetyl-2,3-dideoxy-6,7-O-isopropylidene-d-lyxo-oct-2-en-4-ulosonate, which can isomerise into the corresponding Z isomers. 相似文献
14.
The rate of allelism of lethal genes in a geographically structured population 总被引:2,自引:1,他引:1
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Yokoyama S 《Genetics》1979,93(1):245-262
The expected rate of allelism, E[I(x)], of lethal genes between two colonies with distance x in a structured population is studied by using one- and two-dimensional stepping-stone models. It is shown that E[I(x)] depends on the magnitude of selection in heterozygous condition (h), the rate of migration among adjacent colonies (m), the number of loci which produce lethal mutations (n) and the effective population size of each colony (N).——E[I(x)] always decreases with distance x. The rate of decrease is affected strongly by the magnitude of m. The rate of decrease is faster when m is small. E[I(x)] also decreases with increasing N and n. The effect of h on E[I(x)] is somewhat complicated. However, E[I(0)] is always smaller when h is small than when it is large.——For large x, the following approximate formulae may be obtained: (see PDF) where q and Var (q) are the mean and the variance of gene frequencies in each colony, t is approximated as t=h, (see PDF), -h for the partially recessive, completely recessive, and overdominant lethals, respectively, and C0 is a function of m and t. It is clear that E[I(x)] declines exponentially with x in a one-dimensional habitat. The decrease E[I(x)] is faster in a two-dimensional habitat than in a one-dimensional habitat. The present result is applied to some of the existing data and the estimation of population parameters is also discussed. 相似文献
15.
Yan Hu Brian L. Ellis Ying Y. Yiu Melanie M. Miller Joseph F. Urban Linda Z. Shi Raffi V. Aroian 《PloS one》2013,8(7)
Soil-transmitted helminths are parasitic nematodes that inhabit the human intestine. These parasites, which include two hookworm species,
Ancylostoma
duodenale
and Necator americanus, the whipworm
Trichuris
trichiura
, and the large roundworm
Ascaris
lumbricoides
, infect upwards of two billion people and are a major cause of disease burden in children and pregnant women. The challenge with treating these diseases is that poverty, safety, and inefficient public health policy have marginalized drug development and distribution to control infection in humans. Anthelmintics (anti-worm drugs) have historically been developed and tested for treatment of non-human parasitic nematodes that infect livestock and companion animals. Here we systematically compare the in vitro efficacy of all major anthelmintic classes currently used in human therapy (benzimidazoles, nicotinic acetylcholine receptor agonists, macrocyclic lactones, nitazoxanide) against species closely related to human parasitic nematodes-Ancylostoma ceylanicum,
Trichuris
muris
, and
Ascaris
suum
--- as well as a rodent parasitic nematode used in veterinary drug discovery,
Heligmosomoides
bakeri
, and the free-living nematode Caenorhabditis elegans. Extensive in vitro data is complemented with single-dose in vivo data in three rodent models of parasitic diseases. We find that the effects of the drugs in vitro and in vivo can vary greatly among these nematode species, e.g., the efficacy of albendazole is strong on A. ceylanicum but weak on
H
. bakeri
. Nonetheless, certain commonalities of the in vitro effects of the drugs can be seen, e.g., nitazoxanide consistently shows an all-or-nothing response. Our in vitro data suggest that further optimization of the clinical efficacy of some of these anthelmintics could be achieved by altering the treatment routine and/or dosing. Most importantly, our in vitro and in vivo data indicate that the hookworm A. ceylanicum is a particularly sensitive and useful model for anthelmintic studies and should be incorporated early on in drug screens for broad-spectrum human soil-transmitted helminth therapies. 相似文献
16.
A critical and annotated catalogue of 72 types of Chrysididae (Hymenoptera) belonging to 53 species and subspecies housed in the Swedish Museum of Natural History is given. The lectotypes of Chrysis
diversa Dahlbom, 1845, Chrysis
soror Dahlbom, 1854, Chrysura
sulcata Dahlbom, 1845 and Holopyga
amoenula Dahlbom, 1845 are designated. The previous lectotype of Chrysis
diversa Dahlbom, 1845 is set aside. Five new synonymies are proposed: Chrysis
elegans
var.
smaragdula Trautmann, 1926 (currently Chrysis
elegans
ssp.
interrogata Linsenmaier, 1959 repl. name for smaragdula Trautmann, nec Fabricius, 1775), syn. n. of Chrysis
confluens (Dahlbom, 1845); Chrysis
eximia Mocsáry, 1889, syn. n. of Chrysis
poecila Mocsáry, 1889; Chrysis
pyrrhina Dahlbom, 1845, syn. n. of Chrysis
erythromelas Dahlbom, 1845; Chrysis
separata Trautmann, 1926, syn. n. of Chrysis
lateralis Dahlbom, 1845; Chrysis
sicula Abeille de Perrin, 1877, syn. n. of Chrysis
erythromelas Dahlbom, 1845. Chrysis
serena Radoszkowski, 1891 is the first available name for Chrysis
pyrrhina
sensu
auctorum. Chrysis
erythromelas Dahlbom, 1845 is revaluated as valid species. The neotype of Chrysis
inaequalis Dahlbom, 1845 is designated in the Linsenmaier collection (NMLS). Illustrations of 34 types are given. 相似文献
17.
Taku Fujiwara Yutaka Terao Tomonori Hoshino Shigetada Kawabata Takashi Ooshima Shizuo Sobue Shigenobu Kimura Shigeyuki Hamada 《FEMS microbiology letters》1998,161(2):331-336
Three glucosyltransferase (GTase) genes (gtfB, gtfC and gtfD) were cloned and sequenced from clinically isolated strains of Streptococcus mutans MT8148 (serotype c), MT4239 (c), MT4245 (e), MT4467 (e) and MT4251 (f), respectively. Comparison of the gtf genes revealed that interstrain difference of gtfB and gtfD was limited, while gtfC showed significant interstrain variations. Similar to gtfB and gtfD, gtfC possessed five direct repeats composed of homologous unit in the carboxyl-terminal portion. The repeating unit consisted of 63–65 amino acid residues and is responsible for glucan binding. The gtfC gene from S. mutans MT4245 lacked the fourth unit. Multiple alignment with the gtf sequence of strain GS-5 (c) revealed several changes in these gtf genes due to frameshift mutations. The peptides encoded by the gtfB, gtfC and gtfD genes of GS-5 were 1, 80, and 32 amino acid residues shorter than those of the test strains except strain MT4245. 相似文献
18.
An updated checklist of the superfamilies Oestroidea and Hippoboscoidea recorded from Finland is presented. The checklist covers the following families: Calliphoridae, Rhiniidae, Sarcophagidae, Rhinophoridae, Tachinidae, Oestridae and Hippoboscidae. 相似文献
19.
Gyu Tae Park Jagadeesh Sundaramoorthy Jeong-Dong Lee Jeong Hoe Kim Hak Soo Seo Jong Tae Song 《PloS one》2015,10(11)
The wide range of flower colors in soybean is controlled by six independent loci (W1, W2, W3, W4, Wm, and Wp). Among these loci, mutations in the W3 locus under the w4 allelic background (i.e., w3w4) produce near-white flowers, while the W3w4 genotype produces purple throat flowers. Although a gene encoding dihydroflavonol 4-reductase, DFR1, has been known to be closely associated with the W3 locus, its molecular identity has not yet been characterized. In the present study, we aimed to determine whether DFR1 is responsible for allelic variations in the W3 locus. On the basis of the sequence of a DFR probe, Glyma.14G072700 was identified as a candidate gene for DFR1, and nucleotide sequences of Glyma.14G072700 from cultivars with previously validated genotypes for the W3 locus were determined. As a result, a number of nucleotide polymorphisms, mainly single-base substitutions, between both coding and 5′-upstream region sequences of the W3 and w3 alleles were identified. Among them, an indel of 311-bp in the 5′-upstream region was noteworthy, since the Glyma.14G072700 in all the w3 alleles examined contained the indel, whereas that in all the W3 alleles did not; the former was barely expressed, but the latter was well expressed. These results suggest that Glyma.14G072700 is likely to correspond to DFR1 for the W3 locus and that its expression patterns may lead to allelic color phenotypes of W3 and w3 alleles under the w4 allelic background. 相似文献
20.
Four Old World species of Pheidole ants contain different mixtures of farnesene-type hydrocarbons in their poison apparatus, and the mixture is different between the minor and major workers within a species. A bishomofarnesene (C17H28) provides approximately half of the secretion of the Dufour glands of minor workers of Pheidole pallidula. (Z,E)-α-Farnesene constituted 96% of the Dufour secretion of major workers of P. pallidula, but only 20% of that of minors. The Dufour glands of minor workers of Pheidole sinaitica contain a mixture of farnesene homologues with (Z,E)-α-farnesene and the bishomofarnesene also found in P. pallidula predominant. The mixture in major workers was similar but had, in addition, a small amount of (E)-β-farnesene. The Dufour glands of Pheidole teneriffana minors contain chiefly the same bishomofarnesene found in P. pallidula and P. sinaitica while major workers contain (Z,E)-α-farnesene. Pheidole megacephala minor workers contained small amounts of eight farnesenes, while major workers contained essentially no farnesenes. The poison glands of minor workers of P. pallidula contain 3-ethyl-2,5-dimethylpyrazine. No pyrazine compounds were found in the major workers of P. pallidula or the minor workers of P. sinaitica. The poison glands of the major workers of P. sinaitica contained larger amounts of tetra-substituted pyrazines. No pyrazines were found in the poison reservoirs of major or minor workers of P. teneriffana or P. megacephala. 相似文献