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1.
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This paper describes the identification and functional role of late gene products of bacteriophage Mu, including an analysis of the structural proteins of the Mu virion.In vitro reconstitution of infectious phage particles has shown that four genes (E, D, I, J) control the formation of phage heads and that a cluster of eight genes (K, L, M, N, P, Q, R, S) controls the formation of phage tails.Sodium dodecyl sulphate/polyacrylamide gel electrophoresis of Mu polypeptides synthesized in Escherichia coli minicells infected by Mu phages carrying amber mutations in various late genes has resulted in the identification of the products of gene C (15.5 × 103Mr); H (64 × 103Mr); F (54 × 103Mr); G (16 × 103Mr); L (55 × 103Mr); N (60 × 103Mr); P (43 × 103Mr) and S (56 × 103Mr). Minicells infected with λpMu hybrid phages and deletion mutants of Mu were used to identify polypeptides encoded by the V-β region of the Mu genome. These are the products of genes V, W or R (41.5 × 103Mr, and 45 × 103Mr); U (20.5 × 103Mr) and of genes located in the β region (24 × 103Mr (gpgin) and 37 × 103Mr (possibly gpmom)).Analytical separation of the proteins of the Mu virion revealed that it consists of a major head polypeptide with a molecular weight of 33 × 103, a second head polypeptide of 54 × 103 (gpF) and two major tail polypeptides with molecular weights of 55 × 103 and 12.5 × 103 (gpL and gpY, respectively). In addition, there are five minor components of the tail (including gpN, gpS and gpU) and approximately seven minor components of the head structure of the virion (including gpH).  相似文献   

3.
The following cyclic compounds were oxidized at 4° by means of aqueous sodium peroxide in large excess: 2,3,4,6/5-pentahydroxycyclohexanone (1); xylo-pentahydroxy-2-cyclohexen-l-one (2); xylo-trihydroxycyclohexane-1,2,3-trione (3); reductic acid (4); and ninhydrin (5). On oxidation, 1, 2, and 3 gave carbon dioxide, formic acid, and oxalic acid; in addition, 1 yielded DL-glucaric acid, and 2 and 3 afforded xylaric acid. Compound 4 gave almost equimolecular quantities of carbon dioxide and succinic acid. In addition to a small amount of formic acid, compound 5 gave carbon dioxide and phthalic acid in yields of 92 and 95%, respectively. Reaction mechanisms are proposed.  相似文献   

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5.
Microbial transformation of ursolic acid (1) by Bacillus megaterium CGMCC 1.1741 was investigated and yielded five metabolites identified as 3-oxo-urs-12-en-28-oic acid (2); 1β,11α-dihydroxy-3-oxo-urs-12-en-28-oic acid (3); 1β-hydroxy-3-oxo-urs-12-en-28, 13-lactoe (4); 1β,3β, 11α-trihydroxyurs-12-en-28-oic acid (5) and 1β,11α-dihydroxy-3-oxo-urs-12-en-28-O-β-d-glucopyranoside (6). Metabolites 3, 4, 5 and 6 were new natural products. Their nitric oxide (NO) production inhibitory activity was assessed in lipopolysaccharide (LPS) – stimulated RAW 264.7 cells. Compounds 3 and 4 exhibited significant activities with the IC50 values of 1.243 and 1.711 μM, respectively. A primary structure-activity relationship was also discussed.  相似文献   

6.
All of the known species of the Chinese endemic subgenus Pterostichus (Circinatus) are revised, keyed, and illustrated. Eleven new species and one new subspecies are described: Pterostichus adelphus sp. n. (Sichuan: Meigu, N28.66°, E103.06°); Pterostichus ailaoicus sp. n. (Yunnan: Xinping, N23.94°, E101.50°); Pterostichus camelus sp. n. (Sichuan: Mianning, N28.97°, E102.16°); Pterostichus dimorphus sp. n. (Yunnan: Dayao, N26.08°, E101.03°); Pterostichus maitreya sp. n. (Guizhou: Fanjingshan, N27.90°, E108.70°); Pterostichus miao sp. n. (Guangxi: Maoershan, N25.87°, E110.41°); Pterostichus tumulus sp. n. (Guizhou: Fanjingshan, N27.90°, E108.70°); Pterostichus wangjiani sp. n. (Yunnan: Dongchuan, N26.08°, E102.87°); Pterostichus yan sp. n. (Hubei: Shennongjia, N31.47°, E110.39°); Pterostichus yuxiaodongi sp. n. (Sichuan: Wolong, N30.99°, E103.15°); Pterostichus zhygealu sp. n. (Sichuan: Meigu, N28.67°, E103.05°); and Pterostichus cavazzutianus mianningensis subsp. n. (Sichuan: Mianning, N28.97°, E102.16°). Pterostichus cavazzutianus is proposed as a replacement name for Pterostichus cavazuttii Allegro and Sciaky 2010, preoccupied by Pterostichus (Sinosteropus) barbarae cavazuttii Sciaky and Facchini 2003. A lectotype is designated for Pterostichus baenningeri Jedlička 1931. Two species, Pterostichus schuelkei Sciaky & Wrase and Pterostichus wenxianensis Allegro & Sciaky, are moved from the subgenus Circinatus to Morphohaptoderus. An infra-subgeneric taxonomy is proposed for the subgenus Circinatus with four species groups. The male endophallus characters for most species of Circinatus were well studied, with three types of endophallus defined. A phylogenetic analysis based on adult morphological characters confirmed the infra-subgeneric classification and clarified some of the relationships among species. Two main lineages within Circinatus were identified from the phylogenetic analyses. Three of the four species groups were monophyletic, whereas the fourth group was paraphyletic.  相似文献   

7.
Otiorhynchus (Podonebistus) korotyaevi sp. n., (Proremus) karsavurani sp. n., and O. (Proremus) temeli sp. n. from northeastern Turkey are described. O. kirschi is transferred from the genus Simo (= Homorhythmus) to the genus Otiorhynchus (subgenus Proremus); O. madari, from the genus Cirrorhynchus to the genus Otiorhynchus (subgenus Motilacanus); and O. kataevi, from the subgenus Nilepolemis to the subgenus Otismotilus. New data on the morphology and distribution of O. cataphractus, O. latinasus, O. terrifer, O. pipitzi, O. angustifrons, O. jarpachlinus, and O. sculptirostris are given. Lectotypes of O. lederi, O. erivanensis, O. diotus, O. terrifer, O. kirschi, and O. madari are designated.  相似文献   

8.
There is no general agreement on relationships within Xylophagoidea (Diptera, Brachycera). The musculature of the male genitalia of Xylophagus cinctus (De Geer) (Xylophagidae, the most primitive family of Brachycera) is described and compared with that of some other Xylophagoidea: Exeretonevridae (Exeretonevra angustifrons Hardy), Coenomyiidae (Anacanthaspis biafasciata Röder), and Rhagionidae (Rhagio montanus Becker, Chrysopilus dives Loew, and Ch. helvolus Meigen) discussed earlier (Ovtshinnikova, 1989, 1998; Palmer et al., 2000). In spite of the differences in the structure of the genital sclerites, Xylophagidae possess all the muscles found in Coenomyiidae and Rhagionidae. The musculature of the male genitalia of Xylophagus cinctus includes two muscle pairs of the aedeagus sheath (M1 and M2); three muscle pairs of the ejaculatory complex (M30, M31, and M32); one muscle pair of the gonocoxites (M33); two muscle pairs of the gonostyli (M27 and M28); one muscle pair of the proctiger (M21), one muscle pair of the cerci (M29); two pairs of the tergosternal muscles (M5 1 and M5 2); and two pairs of the pregenital muscles (M18 and M19). Muscles of the family Exeretonevridae are mostly the same, except for the muscles of the cerci M29, proctiger M29, and pregenital muscles M18 and M19, that are subdivided into two parts. This fact and also a different degree of the development of muscles M32 and M5 2 clearly distinguish Exeretonevridae from closely related families. The attachment places of the muscles of the aedeagus sheath M2 and of the gonostyli M28, as well as the split character of the tergosternal muscle pair M5 1 makes it possible to distinguish two sister groups, Xylophagidae plus Exeretonevridae, versus Coenomyiidae plus Rhagionidae. It should be noted that the muscles of the male genitalia of Xylophagidae, Exeretonevridae, Coenomyiidae, and Rhagionidae possess similar plesiomorphic characters, and these families should be united into the superfamily Xylophagoidea. This superfamily is the most primitive superfamily of Brachycera Orthorrhapha and possesses the most stable set and arrangement of male genital muscles within the entire suborder. An improved dendrogram of the phylogenetic relationships between the known groups of Xylophagoidea is proposed on the basis of the structure of male genital muscles.  相似文献   

9.
The insect SNMP gene family   总被引:1,自引:0,他引:1  
SNMPs are membrane proteins observed to associate with chemosensory neurons in insects; in Drosophila melanogaster, SNMP1 has been shown to be essential for the detection of the pheromone cis-vaccenyl acetate (CVA). SNMPs are one of three insect gene clades related to the human fatty acid transporter CD36. We previously characterized the CD36 gene family in 4 insect Orders that effectively cover the Holometabola, or some 80% of known insect species and the 300 million years of evolution since this lineage emerged: Lepidoptera (e.g. Bombyx mori, Antheraea polyphemus, Manduca sexta, Heliothis virescens, Helicoverpa assulta, Helicoverpa armigera, Mamestra brassicae); Diptera (D. melanogaster, Drosophila pseudoobscura, Aedes aegypti, Anopheles gambiae, Culex pipiens quinquefasciatus); Hymenoptera (Apis mellifera); and Coleoptera (Tribolium castaneum). This previous study suggested a complex topography within the SNMP clade including a strongly supported SNMP1 sub-clade plus additional SNMP genes. To further resolve the SNMP clade here, we used cDNA sequences of SNMP1 and SNMP2 from various Lepidoptera species, D. melanogaster and Ae. aegypti, as well as BAC derived genomic sequences from Ae. aegypti as models for proposing corrected sequences of orthologues in the D. pseudoobscura and An. gambiae genomes, and for identifying orthologues in the B. mori and C. pipiens q. genomes. We then used these sequences to analyze the SNMP clade of the insect CD36 gene family, supporting the existence of two well supported sub-clades, SNMP1 and SNMP2, throughout the dipteran and lepidopteran lineages, and plausibly throughout the Holometabola and across a broad evolutionary time scale. We present indirect evidence based on evolutionary selection (dN/dS) that the dipteran SNMPs are expressed as functional proteins. We observed expansions of the SNMP1 sub-clade in C. pipiens q. and T. castaneum suggesting that the SNMP1s may have an expanded functional role in these species.  相似文献   

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Bioassay-guided fractionation of stems of Engelhardia roxburghiana led to isolation of: four diarylheptanoids, engelheptanoxides A–D (14); two cyclic diarylheptanoids, engelhardiols A (5) and B (6); one naphthoquinone dimer, engelharquinonol (7); and one 1-tetralone, (4S)-4,6-dihydroxy-1-tetralone (8), along with 24 known compounds (932). The structures of 18 were by spectroscopic analysis. Compounds 5, 6, 13, 22, and 23 showed antitubercular activity against Mycobacterium tuberculosis H37Rv with MIC values of 72.7, 62.1, 9.1, 15.3, and 70.1 μM, respectively.  相似文献   

12.
Squaliforme sharks are a common but relatively vulnerable bycatch in many deep water fisheries. Eleven species of squaliforme shark are commonly caught at depths of 200–1200 m on Chatham Rise, New Zealand, and their diversity suggests they might occupy different niches. The diets of 133 Deania calcea and 295 Squalus acanthias were determined from examination of stomach contents. The diet of D. calcea was characterised by mesopelagic fishes, and S. acanthias by benthic to pelagic fishes, but was more adaptive and included likely scavenging. Multivariate analyses found the most important predictors of diet variability in S. acanthias were year, bottom temperature, longitude, and fish weight. The diet of the nine other commonly caught squaliforme sharks was reviewed, and the spatial and depth distribution of all species on Chatham Rise described from research bottom trawl survey catches. The eleven species had a variety of different diets, and depth and location preferences, consistent with niche separation to reduce interspecific competition. Four trophic groups were identified, characterised by: mesopelagic fishes and invertebrates (Centroselachus crepidater, D. calcea, and Etmopterus lucifer); mesopelagic and benthopelagic fishes and invertebrates (Centroscymnus owstoni, Etmopterus baxteri); demersal and benthic fishes (Centrophorus squamosus, Dalatias licha, Proscymnodon plunketi); and a generalist diet of fishes and invertebrates (S. acanthias). The trophic levels of the species in each of the four groups were estimated as 4.18–4.24, 4.20–4.23, 4.24–4.48, and 3.84 respectively. The diet of Oxynotus bruniensis and Squalus griffini are unknown. The different niches occupied by different species are likely to influence their vulnerability to bottom trawl fisheries. Some species may benefit from fisheries through an increased availability of scavenged prey.  相似文献   

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14.
Leishmaniasis and fungal infections are significant diseases impacting worldwide public health. Treatments have developed greatly over time, however, there is a necessity to discover less toxic drugs, which have greater efficacy and are more economically accessible. This work conducted a screening of Cerrado species extracts: Connarus suberosus Planch. (Connaraceae), Neea theifera Oerst. (Nyctaginaceae) and Myrcia linearifolia Cambess. (Myrtaceae) against Leishmania (Leishmania) amazonensis, dermatophytes and yeasts. Leishmanicidal and antifungal tests were conducted using MTT colorimetric assay and CLSI methodology, respectively. Connarus suberosus extracts presented the most promising results against the aforementioned microorganisms, which has not been described in the literature. The root bark EtOAc extract was selected for chemical fractionation resulting in a mixture of rapanone (1) and a previously unreported compound named as suberonone (2); a mixture of β-sitosterol (3) and stigmasterol (4); oleic acid (5); geranilgeraniol (6); and two derivatives obtained from 1 and 2 mixture. The rapanone and suberonone mixture demonstrated a MIC of 15.62 μg/mL against Candida albicans ATCC 10231.  相似文献   

15.
We performed molecular phylogenetic analyses of four morphotypes of the benthic foraminiferal genus Bulimina (B. aculeata, B. marginata f. marginata, B. marginata f. denudata, and B. elongata) based on sequences of internal transcribed spacer region of ribosomal DNA (ITS rDNA). Six genetically distinct phylotypes were revealed by our phylogenetic analyses. The six phylotypes basically correspond to the fundamental morphotypes: clades A + B (B. aculeata); clade C (B. elongata); clade D (B. marginata f. denudata); clade E (B. marginata f. marginata genotype 1); and clade F (B. marginata f. marginata genotype 2). All six phylotypes are well distinguished, except phylotype B, which shows only little sequence divergence compared to clade A, possibly indicating that genetic differentiation is in progress. Morphological characters including the direction, placement, and shape of spines, the angle of undercutting of chamber periphery, and the roundness of the chambers were stable among specimens of each clade. In contrast, the length and density of spines, and chamber size, were variable within each clade. These intermediate morphological characters may reflect ecophenotypic variation. Our study clearly shows that the examined B. acuelata, elongata, and denudata morphospecies are genetically separated and that B. marginata is a species complex comprising several genotypes. A novel phylotype represent different morphotype compare to B. marginata f. marginata that can be distinguished based on differences of chamber angularity, the direction, placement, and shape of spines, and test dimensions.  相似文献   

16.
Reduction of RuQ3 (1a, Q = 8-quinolinolato) with Zn/Hg in the presence of various π-acceptor ligands in ethanol affords RuQ2L2 (L2 = (dimethylsulfoxide)2 (2); (4-picoline)2 (3); N,N′-dimethyl-1,4-diazabuta-1,3-diene, dab (4); cyclooctadiene, COD (5); norborna-2,5-diene, nbd (6)). Compound 6 is isolated as an equimolar mixture of cis,trans (6a) and trans,cis (6b) isomers, which can be separated by column chromatography. DFT calculations have been performed on 6a and 6b. Oxidation of 3 and 6b affords the corresponding ruthenium(III) species 7 and 8, respectively. The structures of 2, 3, 4 and 6 have been determined by X-ray crystallography.  相似文献   

17.
《Journal of Asia》2019,22(3):655-665
New taxonomical acts are proposed in eastern Palaearctic and Oriental Chrysomelidae: Aetheanta higuchii (Kimoto and Takizawa 1981) = Smaragdina bothrionota Tan 1987 (syn. nov.); Physosmaragdina nigrifrons (Hope 1843) = Gynandrophthalma subsignata Fairmaire 1888 (syn. nov.); Smaragdina symmetria Tan 1988 = Aetheomorpha schmidti Medvedev 2003 (syn. nov.); Arthrotus malaisei (Bryant, 1954) (comb. nov.); Charaea sikanga (Gressitt and Kimoto 1963) = Luperus aenescens Weise 1889 (syn. nov.) = Taphinellina grahami Wilcox 1973 (syn. nov.); Dercetina purpurea (Bryant, 1954) (comb. nov.); Gallerucida chunia Maulik 1936 = Gallerucida birmanica Bryant, 1954 (syn. nov.); Hoplasoma sexmaculatum (Hope 1831) = Mimastra bistrimaculata Medvedev, 2015 (syn. nov.); Miltina Chapuis 1875 = Liroegala Medvedev, 2015 (syn. nov.); Mimastra Baly 1865 = Neoatysa Abdullah and Qureshi 1968 (syn. nov.); Mimastra shahidi (comb. nov.); Mimastra davidis (Fairmaire, 1878) (valid species) = Mimastra limbata Baly 1879 (syn. nov.); Munina blanchardi (Allard 1891) (comb. nov.) = Munina donacioides Chen, 1976 (syn. nov.) = Munina flavida Yang and Yao, 1997 (syn. nov.); Paraplotes Laboissière, 1933 = Shensia Chen 1964 (syn. nov.); Paraplotes antennalis Chen 1942 = Shensia parvula Chen 1964 (syn. nov.); Paraspitiella maculata (Bryant, 1954) (comb. nov.) = Paraspitiella nigrinotum Yang, 2004 (syn. nov.); Parexosoma sikanga (Gressitt and Kimoto 1963) (comb. nov.); Paridea Baly 1886 = Neosastra Abdullah and Qureshi 1968 (syn. nov.); Paridea (Paridea) octomaculata (Baly 1886) = Neosastra murreeiensis (syn. nov.); Altica Geoffroy 1762 = Neoclitena Abdullah and Qureshi 1968 (syn. nov.); Altica simplex (comb. nov., nomen dubium). New country records of Chrysomelidae from Palaearctic and Oriental Regions are provided.  相似文献   

18.
Distributional patterns of South American species of aquatic and semiaquatic Heteroptera from the Chaco biogeographic province were analyzed. Based on a track analysis of 60 species of Belostomatidae, Corixidae, Micronectidae, and Gerridae, five generalized tracks were found:(1) Bolivia, and northwestern and central Argentina (Belostoma dallasi, Ectemnostega montana, E. quechua, E. stridulata, E. venturii, Sigara tucma, S. yala, Tenagobia pulchra, Eurygerris fuscinervis, and Trepobates taylori); (2) southern Brazil, eastern Bolivia, Paraguay, and northeastern Argentina (Belostoma bosqi, Heterocorixa brasiliensis, Tenagobia selecta tarahui, and T. schadei); (3) southeastern Brazil and northeastern Argentina, determined by Belostoma candidulum, B. testaceopallidum, Heterocorixa nigra, Sigara hungerfordi, Brachymetra furva,Halobatopsis spiniventris, Metrobates plaumanni plaumanni, and M. vigilis; (4) southeastern Brazil, Uruguay, and central western Argentina (Belostoma cummingsi, B. martini, Sigara argentiniensis, Tenagobia fuscata, and T. carapachay); and (5) southern (Trichocorixa milicorum, Sigara santiagiensis, and S. forciceps). Three panbiogeographic nodes have been determined:(1) northeastern Argentina, in the intersection of generalized tracks 2 and 3; (2) central Argentina, in the intersection of generalized tracks 1 and 4; and (3) central Argentina, in the intersection of generalized tracks 4 and 5. In spite of these complex patterns, these results show that the Chaco province appears to be a natural biogeographic area.  相似文献   

19.
The aim of this study was to evaluate the cytotoxic potential of Aristolochia foetida Kunth. Stems and leaves of A. foetida Kunth (Aristolochiaceae) have never been investigated pharmacologically. Recent studies of species of the Aristolochiaceae family found significant cytotoxic activities. Hexane, dichloromethane, ethyl acetate and methanol extracts were analyzed by 1H NMR and GC–MS to know the metabolites in each extract. In GC–MS analysis, the main compounds were methyl hexadecanoate (3); hexadecanoic acid (4); 2-butoxyethyl dodecanoate (9); ethyl hexadecanoate (20); methyl octadeca-9,12,15-trienoate (28) and (9Z,12Z,15Z)-octadeca-9,12,15-trienoic acid (40). The results showed a significant reduction in cell viability of the MCF-7 (breast cancer) cell line caused by organic extracts in a dose-dependent manner. The cytotoxicity activity of the dichloromethane extract from the stems (DSE) showed IC50 values of 45.9 μg/mL and the dichloromethane extract of the leaves (DLE) showed IC50 values of 47.3 μg/mL. DSE and DLE had the highest cytotoxic potential in an in vitro study against the MCF-7 cell line and non-tumor cells obtained from the bovine mammary epithelial (bMECs). DSE and DLE induced a loss in mitochondrial membrane potential (ΔΨm) and can cause cell death by apoptosis through the intrinsic pathway in the MCF-7 cell line. DSE and DLE are cytotoxic in cancer cells and cause late apoptosis. Higher concentrations of DSE and DLE are required to induce a cytotoxic effect in healthy mammary epithelial cells. This is the first report of the dichloromethane extract of A. foetida Kunth that induces late apoptosis in MCF-7 cancer cells and may be a candidate for pharmacological study against breast cancer.  相似文献   

20.
Breast cancer (BC) is one of the most common oncological diseases in the world and has a complex polygenic multifactorial character. The simultaneous analysis of a large number of medium- and low-penetrance genes in the genesis of the sporadic forms of BC makes it possible to more accurately predict the individual risk of this disease, and the analysis of their intergenic associations will help to identify the most significant interactions between several of them. This would significantly simplify further screening studies. In this study, we analyzed all possible combinations of pathogenetically significant polymorphic variants for the key genes involved in (1) repair systems (XRCC1, XRCC3, and PALB2); (2) biotransformation of xenobiotics (NAT2, EPHX1, GSTP1, GSTT1, and GSTM1); (3) cell cycle control (HMMR, TP53); and (4) folate cycle (MTHFR) among patients from Belarus (eastern European region) with the sporadic forms of BC and in the control group. The combinations of genotypes (genetic profile) significantly modifying the risk of sporadic BC were identified using the multifactor dimensionality reduction (MDR). The genetic profile (combinations of genotypes) leading to a significant increase in the risk of sporadic BC is the presence of the G allele in SNP p.I105V (GSTP1), the T allele in SNP p.T241M (XRCC3), and the AA genotype in SNP p.E429A (MTHFR).  相似文献   

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