中国梨头蜂科种类记述(膜翅目 :青蜂总科)(英文)

梨头蜂科是一个小科 ,为珍稀类群 ,全世界仅知 2属 3 3种 (包括 2种化石种类 )。本文对中国梨头蜂标本进行了全面系统的研究 ,共记录中国梨头蜂科 2属 6种。其中 ,克氏安梨头蜂Ampulicomorphacol linsiOlmi,1 995和柯氏梨头蜂EmbolemuskrombeiniOlmi,1 995为中国新记录。     

A new species of the genus Anteon Jurine (Hymenoptera,Dryinidae) from Thailand

A new species of Anteon Jurine, 1807 is described from Thailand, Nan Province: Anteon huettingeri sp. n. Morphologically the new species is similar to Anteon borneanum Olmi, 1984, Anteon jurineanum Latreille, 1809, Anteon insertum Olmi, 1991, Anteon yasumatsui Olmi, 1984, Anteon sarawaki Olmi, 1984, Anteon thai Olmi, 1984 and Anteon krombeini Olmi, 1984, but it is clearly different for the numerous sensorial processes present on the inner side of the paramere; these processes are absent in the other above species. Published identification keys to the Oriental species of Anteon are modified to include the new species.     

Predicting the potential geographical distribution of parasitic natural enemies of the Dubas bug (Ommatissus lybicus de Bergevin) using geographic information systems

The Dubas bug (Ommatissus lybicus de Bergevin) is a pest species whose entire life cycle occurs on date palms, Phoenix dactylifera L, causing serious damage and reducing date palm growth and yield. Pseudoligosita babylonica Viggiani, Aprostocetus nr. Beatus, and Bocchus hyalinus Olmi are very important parasitic natural enemies of Ommatissus lybicus in northern Oman. In this study, random farms were selected to (a) model the link between occurrences of the Pseudoligosita babylonica, Aprostocetus nr beatus, and Bocchus hyalinus (dependent variables) with environmental, climatological, and Dubas bug infestation levels (the independent variables), and (b) produce distribution and predictive maps of these natural enemies in northern Oman. The multiple R² values showed the model explained 63%, 89%, and 94% of the presence of P. babylonica, A. nr beatus, and Bocchus hyalinus, respectively. However, the distribution of each species appears to be influenced by distinct and geographically associated climatological and environmental factors, as well as habitat characteristics. This study reveals that spatial analysis and modeling can be highly useful for studying the distribution, the presence or absence of Dubas bugs, and their natural enemies. It is anticipated to help contribute to the reduction in the extent and costs of aerial and ground insecticidal spraying needed in date palm plantations.     

A large open reading frame ( orf1995 ) in the chloroplast DNA of Chlamydomonas reinhardtii encodes an essential protein

An open reading frame potentially encoding a protein of 1995 amino acids (orf1995) has been found in the chloroplast genome of the green alga Chlamydomonas reinhardtii. Besides having a short hydrophobic N-terminal domain with five putative transmembrane helices, the predicted orf1995 product is highly basic. orf1995 might be a homologue of the ycf1 gene in land plants, whose function has not yet been determined. Mutants of C. reinhardtii transformed with a disruption of orf1995 remain heteroplasmic for the wild-type and disrupted alleles of this gene, indicating that the orf1995 product is essential for cell survival. Received: 18 August 1996 / Accepted: 24 September 1996     

Preliminary X-ray diffraction analysis of crystals of turnip yellow mosaic virus (TYMV)

Turnip yellow mosaic virus (TYMV) was purified from Chinese cabbage and crystallized in a form that permits high resolution structural analysis using X-ray diffraction. The crystals have a hexagonal bipyramidal morphology and often achieve dimensions of 1.0 × 1.0 × 0.5 mm. The crystals appear to be of hexagonal space group P6₂22 with a = b = 525 Å, c=315 Å, but we cannot strictly rule out the possibility that the space group is P622. They appear different than any crystals of TYMV previously reported. There are three T = 3 virus particles in the unit cell, which implies that one quarter of the particle, or 45 protein subunits, comprises the asymmetric unit of the crystal. Native data have been collected using synchrotron radiation to a resolution of 3.2 Å. © 1995 Wiley-Liss, Inc.     

Effect of ilvBN-encoded α-acetolactate synthase expression on diacetyl production in Lactococcus lactis

 Conversion of pyruvate to α-acetolactate, which is broken down to diacetyl and acetoin, can be catalysed by two α-acetolactate synthases in Lactococcus lactis. The enzyme encoded by the als gene (Als) has previously been shown to have a low affinity for pyruvate, which limits the formation of diacetyl. In this study we have expressed from a plasmid the ilvBN genes, which encode the other α-acetolactate synthase (IlvBN). This plasmid-directed enzyme expression provided up to 3.6-fold increased product formation in the L. lactis MG1363 and IL1403 backgrounds. Plasmid-based expression of the ilvBN genes, in an IL1403 derivative from which the leu.ilv.ald and flanking genes had been deleted, yielded up to 0.1 mM diacetyl whereas the host strain produced none. In addition, IlvBN, with a K _m value of 8.3 mM, was shown to have a greater affinity for pyruvate than does Als. Received: 28 June 1995 / Received revision: 26 September 1995 / Accepted: 29 September 1995     

鄱阳湖湖岸带景观变化

湖岸带是水陆生态系统过渡带,是人类活动最集中的区域之一,也是生态系统较为脆弱的区域。湖岸带具有重要的生态功能,湖岸带研究对于湖泊湿地生态系统保护具有重要意义。利用1995年,2000年,2005年和2010年4个时期的同水位条件下鄱阳湖湿地湖岸带遥感影像,对鄱阳湖湖岸带的景观进行了研究,结果表明,鄱阳湖湖岸带各种景观类型的面积变化显著,2010时期的水体面积较1995年、2000年和2005年时期减少近100km~2,绿地面积2010年较1995年减少近500km~2,建设用地和裸地面积2010年较1995年增加700km~2以上。景观指数变化明显,景观斑块数量逐年上升,最大斑块面积逐年减小,周长面积分形指数逐年加大,辛普森和香浓景观多样性指数逐年增大,表明湖岸带景观破碎化程度逐年加强。通过遥感影像解译结果综合分析,鄱阳湖湖岸带建设用地和裸地增加主要表现在沙化土地面积、交通建设用地面积和居民建筑建设用地的增加有关。     

The parasitoid Gonatopus bartletti reduces presence of plant-pathogenic Spiroplasma kunkelii within the leafhopper vector Dalbulus maidis

Homopteran vectors (e.g., leafhoppers) of plant pathogens are vessels for reproduction of cell wall‐free bacteria. These vectors also serve as hosts for larval parasitoid dipterans, hymenopterans, and strepsipterans. However, no study has explored the relationship among these wall‐free bacteria and parasitoid larvae within the insect host. We studied the corn stunt spiroplasma (CSS), Spiroplasma kunkelii Whitcomb (Mycoplasmatales: Spiroplasmataceae), a bacterium that originated from secondary symbionts that cause corn stunt disease in maize, Zea mays L., and its reproduction in the haemolymph of the corn leafhopper, Dalbulus maidis (Delong and Wolcott) (Homoptera: Cicadellidae). We also studied the dryinid parasitoid Gonatopus bartletti Olmi (Hymenoptera: Dryinidae), the larva of which feeds in the corn leafhopper haemolymph. Our results showed that when CSS and the wasp coexisted in D. maidis, the development of the parasitoid was not affected by S. kunkelii. Parasitoid development was successfully completed when leafhoppers acquired S. kunkelii before or after parasitism and when CSS had median (10 days) and long (20 days) incubation periods in the leafhopper before parasitization. The presence of S. kunkelii did not affect parasitoid development to the adult stage. However, polymerase chain reaction showed that the presence (survival) of S. kunkelii in the leafhopper was negatively affected by the parasitoid larva. Fewer leafhoppers had CSS before and after parasitization compared with leafhoppers that only acquired the CSS. This negative effect helps to explain the high parasitism rate by G. bartletti in D. maidis and the low presence of S. kunkelii in the corn leafhopper when CSS and the wasp parasitoid overlap throughout their geographic distribution. The parasitoid larva may negatively affect S. kunkelii by (1) producing antibacterial peptides that are toxic to CSS; (2) producing teratocytes that take nutrients from the host for larval development, but these nutrients are required by CSS; (3) affecting, indirectly, CSS through other symbiotic microorganisms; and (4) producing proteins with antibacterial activity that are present in the venom of the wasp parasitoid.     

Mitochondrial DNA variation, effective female population size and population history of the endangered Chinese sturgeon, Acipenser sinensis

The anadromous Chinese sturgeon (Acipenser sinensis), mainly endemic to the Yangtze River in China, is an endangered fish species. The natural population has declined since the Gezhouba Dam blocked its migratory route to the spawning grounds in 1981. In the near future, the completion of the Three Gorges Dam, the world's largest hydroelectric project, may further impact this species by altering the water flow of the Yangtze River. Little is currently known about the population genetic structure of the Chinese sturgeon. In this study, DNA sequence data were determined from the control region (D-loop) of the mitochondrial genome of adult sturgeons (n = 106) that were collected between 1995–2000. The molecular data were used to investigate genetic variation, effective female population size and population history of the Chinese sturgeon in the Yangtze River. Our results indicate that the reduction in abundance did not change genetic variation of the Chinese sturgeon, and that the population underwent an expansion in the past. AMOVA analysis indicated that 98.7% of the genetic variability occurred within each year's spawning populations, the year of collection had little influence on the diversity of annual temporary samples. The relative large effective female population size (N _ef) indicates that good potential exists for the recovery of this species in the future. Strikingly, the ratio of N _ef to the census female population size (N _f) is unusually high (0.77–0.93). This may be the result of a current bottleneck in the population of the Chinese sturgeon that is likely caused by human intervention. This revised version was published online in July 2006 with corrections to the Cover Date.     

Formation of sulfate and glucoside conjugates of benzo[e]pyrene by Cunninghamella elegans

 Benzo[e]pyrene is a pentacyclic aromatic hydrocarbon, which, unlike its structural isomer benzo[a]pyrene, is not a potent carcinogen or mutagen. The metabolism of benzo[e]pyrene was studied using the filamentous fungus Cunninghamella elegans ATCC 36112. C. elegans metabolized 65% of the [9, 10, 11, 12-³H]benzo[e]pyrene and unlabeled benzo[e]pyrene added to Sabouraud dextrose broth cultures after 120 h of incubation. Three major metabolites of benzo[e]pyrene were separated by reversed-phase high-performance liquid chromatography. These metabolites were identified by ¹H and ¹³C NMR, UV-visible, and mass spectral analyses as 3-benzo[e]pyrenylsulfate, 10-hydroxy-3-benzo[e]pyrenyl sulfate, and benzo[e]pyrene 3-O-β-glucopyranoside. Received: 7 September 1995/Received revision: 14 November 1995/Accepted: 11 December 1995     

Nutritional interdependence betweenThermoanaerobacter thermohydrosulfuricus andClostridium thermocellum

Thermoanaerobacter thermohydrosulfuricus strain YM3 and Clostridium thermocellum strain YM4, obtained originally as a stable coculture, required yeast extract to grow separately. Cell-free broths of T. thermohydrosulfuricus strain YM3 and C. thermocellum strain YM4 monocultures replaced yeast extract in supporting the growth of strains YM4 and YM3, respectively. T. thermohydrosulfuricus strain YM3 produced vitamin B₆, B₁₂ analog(s), p-aminobenzoic acid and folic acid, which were required by C. thermocellum strain YM4. Likewise, strain YM4 produced niacin-active compound(s), thiamine, and methionine required by strain YM3. Received: 17 March 1995 / Accepted: 27 March 1995     

CFTR: Domains, Structure, and Function

Mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) cause cystic fibrosis (CF) (Collins, 1992). Over 500 naturally occurring mutations have been identified in CF gene which are located in all of the domains of the protein (Kerem et al., 1990; Mercier et al., 1993; Ghanem et al., 1994; Fanen et al., 1992; Ferec et al., 1992; Cutting et al., 1990). Early studies by several investigators characterized CFTR as a chloride channel (Anderson et al.; 1991b,c; Bear et al., 1991). The complex secondary structure of the protein suggested that CFTR might possess other functions in addition to being a chloride channel. Studies have established that the CFTR functions not only as a chloride channel but is indeed a regulator of sodium channels (Stutts et al., 1995), outwardly rectifying chloride channels (ORCC) (Gray et al., 1989; Garber et al., 1992; Egan et al., 1992; Hwang et al., 1989; Schwiebert et al., 1995) and also the transport of ATP (Schwiebert et al., 1995; Reisin et al., 1994). This mini-review deals with the studies which elucidate the functions of the various domains of CFTR, namely the transmembrane domains, TMD1 and TMD2, the two cytoplasmic nucleotide binding domains, NBD1 and NBD2, and the regulatory, R, domain.     

Hierarchy and value: An introduction

Martha J. Kaplan. 1995. Neither Cargo Nor Cult: Ritual Politics and Colonial Imagination in Fiji. London and Durham: Duke University Press, xviii + 236 pp.

Martha Mundy. 1995. Domestic Government: Kinship, Community and Polity in North Yemen. London: I.B. Tauris Publishers. 317 pp.

Thomas Csordas (ed.). 1994. Embodiment and Experience: The Existential Ground of Culture and Self. Cambridge: Cambridge University Press. xi + 294 pp.

Philip L. Kohl &; Clare Fawcett (eds). 1995. Nationalism, Politics, and the Practice of Archaeology. Cambridge: Cambridge University Press. xi + 329 pp.

Joanna B. Eicher (ed.). 1995. Dress and Ethnicity: Change Across Space and Time. Oxford: Berg Publishers. xiv + 316 pp.

Anatoly M. Khazanov. 1995. After the USSR: Ethnicity, Nationalism, and Politics in the Commonwealth of Independent States. Madison: The University of Wisconsin Press. 334 pp.

Pertti J. Anttonen &; Reimund Kvideland (eds). 1994. Nordic Frontiers: Recent Issues in the Study of Modern Traditional Culture in the Nordic Countries. Turku: Nordic Institute of Folklore. 238 pp.

Hugo G. Nutini. 1995. The Wages of Conquest: The Mexican Aristocracy in the Context of Western Aristocracies. Ann Arbor: University of Michigan Press. 444 pp.     

Dechlorination of tetrachloroguaiacol by laccase of white-rot basidiomycete Coriolus versicolor

 Degradation of tetrachloroguaiacol is catalyzed by an extracellular enzyme, the laccase of the white-rot fungus Coriolus versicolor. This enzyme catalyzes the dechlorination of tetrachloroguaiacol and release of chloride ions. The pathway for the degradation was deduced from the intermediates produced by purified laccase and ¹⁸O-labeling experiments. The first step is demethylation. The resulting tetrachlorocatechol is dechlorinated to give 2,3,5-trichloro-6-hydroxy-p-benzoquinone, 2,5-dichloro-3,6-dihydroxy-p-benzoquinone, and dichloro-6-hydroxy-p-benzoquinone. Isotopic experiments established the mechanism of dechlorination of tetrachloroguaiacol by laccase. The laccase-catalyzed dechlorination is not caused by oxidative coupling but by nucleophilic substitution in which Cl^- is released by water from cation radicals generated by laccase. Received: 25 August 1995/Received revision: 27 October 1995/Accepted: 20 November 1995     

Relationships between transposable elements based upon the integrase-transposase domains: Is there a common ancestor?

The integrase domain of RNA-mediated elements (class I) and the transposase domain of DNA-mediated transposable elements (class II) were compared. A number of elements contain the DDE signature, which plays an important role in their integration. The possible relationships between mariner-Tc1 and IS elements, retrotransposons, and retroviruses were analyzed from an alignment of this region. The mariner-Tc1 superfamily, and LTR retrotransposons and retroviruses were found to be monophyletic groups. However, the IS elements of bacteria were found in several groups. These results were used to propose an evolutionary history that suggests a common ancestor for some integrases and transposases. Received: 3 July 1995 / Accepted: 9 October 1995     

Cloning and sequence analysis of the highly expressed melanin-synthesizing gene operon from Streptomyces castaneoglobisporus

 Streptomyces castaneoglobisporus HUT6202 overproduces a diffusible melanin-like pigment. An operon, designated mel, containing a gene that encodes tyrosinase, which is involved in the synthesis of melanin pigment, was cloned from the chromosomal DNA of the microorganism into the high-copy plasmid pAK114 and expressed in S. lividans. The tyrosinase activity of the transformed cells was at approximately a 110-fold higher level than that of the same host carrying the plasmid pIJ702, which has the same replication origin as pAK114 and carries the mel operon from S. antibioticus. The sequence analysis of the S. castaneoglobisporus mel operon revealed that an open- reading frame consisting of 378 base pairs(bp), designated ORF378, was found upstream of the tyrosinase gene (TYRC) consisting of 819 bp. In the present study, we constructed a chimeric mel operon consisting of ORF378 from S. castaneoglobisporus and the tyrosinase gene (TYRA) from S. antibioticus. The chimeric mel operon or the S. antibioticus mel operon, which consists of ORF438 and TYRA, expressed the tyrosinase activity in Escherichia coli intracellularly when located under the control of lacZ promoter, and the tyrosinase activity from the former was at a 30-fold higher level than that from the latter. This suggests that the gene contributing to the high expression of the tyrosinase activity in S. castaneoglobisporus is ORF378, rather than TYRC. Received: 12 June 1995/Received revision: 24 July 1995/Accepted: 7 September 1995     

Expression of the Arxula adeninivorans glucoamylase gene in Kluyveromyces lactis

 The glucoamylase gene of the yeast Arxula adeninivorans was expressed in Kluyveromyces lactis by using the GAP promoter from Saccharomyces cerevisiae and a multicopy plasmid vector. The transformants secreted 90.1% of the synthesized glucoamylase into the culture medium. The secreted glucoamylase activities are about 20 times higher in comparison to those of Saccharomyces cerevisiae transformants using the same promoter. Secreted glucoamylase possesses identical N-terminal amino acid sequences to those secreted by A. adeninivorans showing that cleavage of the N-terminal signal peptide takes place at the same site. Biochemical characteristics of glucoamylase expressed by K. lactis and A. adeninivorans are very similar. Received: 12 June 1995/Received revision: 17 July 1995/Accepted: 26 July 1995     

Rhizobium etli cytochrome mutants with derepressed expression of cytochrome terminal oxidases and enhanced symbiotic nitrogen accumulation

 A method to isolate mutants with derepressed expression of cytochrome oxidases and better symbiotic performance is presented. A mutant of Rhizobium etli, CFN030, isolated by its azide-resistant phenotype, was obtained by transposon Tn5-mob mutagenesis. This mutant has a derepressed expression of cytochrome aa₃, higher respiratory activities when cultured microaerobically and an improved symbiotic nitrogen fixation capacity. This phenotype was similar to the previously described mutant CFN037, which was isolated by its increased capacity to oxidize N,N,N′,N′-tetramethyl-p-phenylenediamine (TMPD) [Soberón M et al. (1990) J Bacteriol 172:1676–1680]. We show here that although both mutants have a similar symbiotic phenotype, they are affected in different genes. Strain CFN030 has the Tn5 inserted in the chromosome while in strain CFN037 the transposon was located in plasmid b. Cytochrome spectral analysis of both mutant strains in the post-exponential phase of growth, showed the expression of an additional terminal oxidase (cbb₃) that is not expressed in the wild-type strain. Received: 10 April 1995/Received revision: 21 August 1995/Accepted: 7 September1995     

Earthworm secondary production and N flux in agroecosystems: a comparison of two approaches

Production was estimated for Aporrectodea spp. and Lumbricus spp. populations in corn agroecosystems with a 5-year history of manure or inorganic fertilizer applications during 1994–1995 and 1995–1996. Earthworm biomass and production were greater in manure than inorganic fertilizer plots, although biomass and production declined by about 50% between 1994–1995 and 1995–1996 due to unfavorable climatic conditions. Production was highest during the spring and autumn when soil temperatures were between 4 and 22°C. Production was higher in Lumbricus spp. than Aporrectodea spp. populations due to greater Lumbricus spp. biomass. Aporrectodea spp. production was 3.47–16.14 g ash-free dry weight (AFDW) m^–2 year^–1, while Lumbricus spp. production was 6.09–18.11 g AFDW m^–2 year^–1, depending on the fertilizer treatment and the method used to estimate production. However, production estimates from the instantaneous growth rate method were within 27% of the values calculated using the size-frequency method. Nitrogen flux through earthworms was used to estimate efficiency quotients. Net production efficiency (P/A) ranged from 0.64 to 0.76, assimilation efficiency (A/C) ranged from 0.1 to 0.3, and gross production efficiency (P/C) ranged from 0.06 to 0.22. Annual N flux through earthworm populations was higher in manure than inorganic fertilizer plots, and ranged from 2.95 to 5.47 g N m^–2 year^–1 in 1994–1995 and 1.76 to 2.92 g N m^–2 year^–1 in 1995–1996. The N flux through earthworms represented an amount equivalent to 16–30% of crop N uptake during 1994–1995 and 11–18% of crop N uptake during 1995–1996. We concluded that the effects of earthworms on N cycling in corn agroecosystems were substantial, and that N flux through earthworms was influenced significantly by fertilizer amendments. Received: 20 September 1999 / Accepted: 24 March 2000     

Stereoselectivity of microbial oxygenation of metallocene sulphides with different substituent size and central atom

 Stereoselectivity in the oxidation of ferrocenyl sulphides with several species of microorganisms such as Corynebacterium equi was reversed between (methylthiomethyl)ferrocene and (t-butylthiomethyl)ferrocene, indicating that the size of the side chain could control the stereochemical course of the biooxidation. The size seems to be effective within some limit, because the more bulky compound, (phenylthiomethyl)ferrocene, was a poor substrate. On the other hand, the microbial oxidation of (methylthiomethyl)ruthenocene and -osmocene with Mortierella isabellina and that of (t-butylthiomethyl)ruthenocene and -osmocene with C. equi gave levorotatory sulphoxides (85–97% e.e.), which were all found to have R absolute configuration. These stereoselectivities were the same as those for the corresponding ferrocenyl sulphides. Thus, the central atom of the metallocenic sulphides seems not to affect the stereoselectivity in the biooxidation. The microbial oxidation is a useful method to prepare several kinds of chiral metallocenic sulphoxides with high optical purity. Received: 17 October 1995/Received revision: 5 December 1995/Accepted: 11 December 1995