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A Scleroderma species collected on sandy soil under trees of Lithocarpus edulis in Saitama Prefecture, central Japan, is identified as Scleroderma laeve, a new record for Japan. Macroscopic and microscopic features are given.
Received: May 24, 2002 / Accepted: September 9, 2002
Acknowledgments We thank Ms. Ryoko Onuma, who offered some useful literature on Scleroderma. We are also grateful to Dr. Toshimitsu Fukiharu (Natural History Museum and Institute, Chiba) for his help with preserving
the specimens. For collecting specimens, we are grateful to Ms. Ayano Kimura, Mr. Tomoya Matsuyama, and Mr. Takahiro Uchida.
Correspondence to:T. Kasuya 相似文献
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Ecological diversity and speciation in land snails of the genus Mandarina from the Bonin Islands 总被引:1,自引:0,他引:1
S. Chiba 《Population Ecology》2002,44(3):0179-0187
Endemic land snails of the genus Mandarina of the oceanic Bonin Islands offer an example of habitat and character divergence among closely related species. The molecular
phylogenies of Mandarina show that a divergence of arboreal, semiarboreal, and ground-dwelling species has occurred repeatedly in different times,
areas, and lineages. Ecological diversification is suggested to be important for the coexistence of Mandarina species based on the facts that sympatric species are typically highly differentiated ecologically and morphologically, and
that species occupying similar habitats do not coexist. The ecological diversification of Mandarina has occurred without much genetic divergence compared with that of its mainland relatives. This suggests that morphological
and ecological diversifications are accelerated in depauperate environments where there are fewer competitors and predators.
Although the details of the reproductive isolation mechanisms are not understood and further examination is needed, the rapid
evolution of prezygotic isolation is the main cause of speciation in Mandarina. In particular, ecological diversification may be an effective barrier to gene exchange between two species. Because of incomplete
postmating isolation and the lower genetic divergence among species of Mandarina, breakdowns of reproductive isolation have frequently occurred as a result of habitat change. It is important to estimate
the effect of hybridization on species diversification in future studies.
Received: February 7, 2002 / Accepted: October 22, 2002
Acknowledgments I express my sincere thanks to A. Davison, B.C. Clarke, A. Guiller, D. Thomaz, K. Tomiyama, I. Hayami, and K. Tanabe for
helpful advice and assistance. This study was supported by grants from the Japan Society for the Promotion of Science and
the Nippon Life Insurance Foundation. 相似文献
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Three aryl alcohol oxidases (AAOs; EC 1.1.3.7) I, II, and III from the culture filtrate of a strain of white-rot fungus Pleurotus ostreatus were purified by multistep chromatography. Each of the purified AAOs I, II, and III had the same molecular masses of 70 kDa
and 72 kDa on gel filtration chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, respectively. Their
optimum temperature was 40°C, but their optimum pHs differed slightly. The N-terminal amino acid sequence of AAOs I, II, and
III was determined to be Ala-Asp-Lys-Asp-Tyr-Ile-Val-Val-Gly-Ala, which showed significant similarity to those of Pleurotus eryngii (80% identity) and Pleurotus ostreatus Florida (60% identity).
Received: May 30, 2002 / Accepted: July 10, 2002
Acknowledgment This work was supported in part by a Grant-in-Aid for the Encouragement of Young Scientists (no. 12760117) from the Ministry
of Education, Culture, Sports, Science and Technology, Japan.
Correspondence to:K. Okamoto 相似文献
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Seven species of the genus Lophiostoma were the subject of this study. Among these, Lophiostoma mucosum is described and illustrated as a new species. All other species, L. macrostomum, L. semiliberum, L. arundinis, L. caulium, L. caudatum, and L. winteri, are reported for the first time in Japan. A key to the species of Lophiostoma in Japan is given.
Received: August 5, 2002 / Accepted: November 28, 2002
Acknowledgments We are grateful to Dr. Hideki Takahashi (curator of SAPA) for the loan of fungal material.
Correspondence to:Y. Harada 相似文献
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Schliekelman P 《Journal of mathematical biology》2003,46(2):171-188
With recent advances in molecular genetics, it is likely that releases of genetically modified organisms will be used for
a variety of purposes. In many cases, such systems would utilize organisms that have been modified on multiple genetic loci.
Predicting the effect of such releases will require an understanding of the transient dynamics in the system. However, theoretical
understanding of transient dynamics in multilocus systems is limited, particularly for early generations when gametic disequilibrium
is still high. I derive approximate expressions for marginal allele frequency and marginal two-locus disequilibrium that are
applicable in this initial period, assuming infinite population size, two alleles per locus, and weak viability selection.
I then apply these results to exploring the effect of parameters on the frequency of the resident gamete type in a release
of organisms carrying an autocidal allele on multiple loci. This leads to simple approximate expressions for the optimal number
of loci carrying the autocidal allele (as a function of release size and the degree of natural selection against the alleles)
and the size of release needed to overcome a given level of selection against the released alleles.
Received: 5 March 2001 / Revised version: 10 July 2002 / Published online: 18 December 2002
Current address: Department of Statistics, 204 Statistics Building, University of Georgia, Athens, GA 30602-1952, USA. e-mail:
pdschlie@stat.uga.edu
Key words or phrases: Multilocus – Selection – Transgenic – Pest control – Genetic control
Acknowledgements. I thank Steve Ellner for insight and guidance throughout this project. This research was partially funded by a fellowship
from the College of Agricultural and Life Sciences Foundation of North Carolina State University. 相似文献
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To identify a basidiomycetous fungus isolated from butt rot of Chamaecyparis obtusa, Japanese cypress, its cultural features were examined, and sequences of its nuclear ribosomal 18S and ITS1–5.8S–ITS2 regions
were analyzed. In culture, this fungus is characterized by the occurrence of chlamydospores, blastoconidium-like cells, and
clavate-to-spathulate hyphal ends at the tips of aerial hyphae, and production of a small basidioma on the mycelial mat after
3 months of incubation. The morphological features of the basidioma are identical to those of Phlebia brevispora. Furthermore, molecular data of the sequences of these strains and P. brevispora showed a high level of similarity. These results appear to justify determining the present fungus as P. brevispora. This is the first report of this species for Japan and outside of southeastern USA.
Received: March 11, 2002 / Accepted: September 20, 2002
Acknowledgments We thank Dr. Karen K. Nakasone, Center for Forest Mycology Research, Forest Products Laboratory, USDA Forest Service, for
providing the fungal strains used in this study.
Correspondence to:R. Kondo 相似文献
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Radiation and reticulation: extensive introgressive hybridization in the carabid beetles Ohomopterus inferred from mitochondrial gene genealogy 总被引:1,自引:1,他引:0
T. Sota 《Population Ecology》2002,44(3):0145-0156
In the evolutionary process of an animal lineage, interactions in secondary contacts of differentiated populations and introgressive
hybridization may play an important role. In the Japanese islands, the carabid subgenus Ohomopterus (genus Carabus) exhibits a marked differentiation in body size and genital morphology. Although geographical differentiation is apparent,
two or three species usually coexist at many localities. Their reproductive isolation relies on body size differences, chemical
cues for mate recognition, and a species-specific genital lock-and-key system. However, these isolation mechanisms are not
always effective enough to prevent interspecific hybridization. An initial assessment of the species-level phylogeny with
mitochondrial gene sequences revealed that the gene genealogy is highly inconsistent with the morphology-based taxonomy. A
comparison of mitochondrial and nuclear gene genealogies showed that these are strongly incongruent with each other, while
the nuclear gene genealogy is more consistent with traditional taxonomy, indicating the repeated occurrence of introgression
of mitochondria across species. Here, two different cases of mitochondrial introgression among Ohomopterus species are described in detail, one for parapatric species and the other for sympatric species. First, mitochondrial haplotypes
and sequences were studied in Carabus insulicola and three taxa parapatric with C. insulicola, at least two of which hybridize with C. insulicola naturally. Among the four species studied, directional introgressions of mitochondria across boundary zones were detected.
Second, in the Mt. Kongo area in central Honshu, which harbors five species, introgression of mitochondria among four out
of the five species was detected, despite the apparent absence of on-going natural hybridization. These inferred cases of
mitochondrial introgression indicate that species interactions through hybridization could have played an important role at
various stages in the evolution of Ohomopterus.
Received: April 12, 2002 / Accepted: October 17, 2002
Acknowledgments I am grateful to Alfried P. Vogler for a long-lasting collaboration in the molecular phylogenetic study of Ohomopterus. R. Ishikawa, K. Kubota, M. Ujiie, Y. Takami, and F. Kusumoto have also collaborated at various stages of this study. Thanks
are also due to K. Miyashita, T. Funakoshi, H. Fujimoto, T. Dejima, Y. Nagahata, T. Miyagawa, K. Yodoe, H. Kadowaki, S. Nakamine,
Y. Oka, H. Tanaka, T. Tanabe, K. Kusakari, and T. Okumura for their care of specimens. Supported by grants-in-aid from the
Japan Society for the Promotion of Science (Nos. 09640748, 11304056). 相似文献
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Y. Ono 《Mycoscience》2002,43(5):0421-0439
Nine types with 11 variations of nuclear cycle and associated metabasidium development were distinguished in microcyclic
rust fungi. An additional type was recognized in rust fungi with an expanded life cycle. A significant proportion of rust
fungi with a reduced life cycle is assumed to have lost a sexual genetic recombination process, being either apomictic or
asexual in reproduction. Most species that retain a sexual process in the microcyclic life cycle seem to have become homothallic.
During life cycle evolution by the omission of spore stages, these traits might have had a selective advantage for those species
that had less opportunity to encounter a genetically different but sexually compatible mate because of isolated patchy distribution
or a short growing season. The findings that different populations of a morphologically identifiable species exhibit two or
more distinct patterns of nuclear cycle and different metabasidium development indicate that microcyclic lineages might have
evolved independently and repeatedly from a macrocyclic parental species. Those lineages are morphologically the same but
would differ from each other in their genetics and biology.
Received: July 5, 2002 / Accepted: August 5, 2002
Acknowledgment This work was supported in part by a Grant-in-Aid for Scientific Research (no. 09640744) from the Ministry of Education,
Science and Culture (now the Ministry of Education, Culture, Sports, Science and Technology), Japan.
Correspondence to:Y. Ono 相似文献
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Five species of the genus Lophiotrema are reported in this article. Of these, Lophiotrema vitigenum is described and illustrated as a new species. Three species, L. nucula, L. neohysterioides, and L. vagabundum, are newly added to the Japanease mycoflora. Lophiosphaera orientalis, Nodulosphaeria araucariae, and N. rosae, which had been recorded in Japan, are treated as synonyms of Lophiotrema fuckelii. A key to the species of Lophiotrema in Japan is given.
Received: October 9, 2002 / Accepted: January 20, 2003
Acknowledgments We are grateful to Drs. Shuhei Tanaka (curator of YAM) and Ken Katumoto for the loan of fungal material.
Correspondence to:K. Tanaka 相似文献
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Seven strains representative of Polysphondylium pallidum were examined in terms of mating relationship and morphology. By mating tests, two heterothallic mating groups were detected.
By morphological comparisons, they were clearly different in number of branches and in shape of bases and tip cells of sorophores.
These results suggested that these two mating groups were distinct taxa.
Received: January 23, 2002 / Accepted: August 30, 2002
Present address:Kanagawa Prefectural Museum of Natural History, Odawara, Kanagawa, Japan (visiting researcher)
Acknowledgments I thank Dr. James C. Cavender, Department of Environmental and Plant Biology, Ohio University, Athens, OH, USA, for providing
the cultures of three strains, V-1, WS320, and WS543.
Correspondence to:H. Hagiwara 相似文献
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Twelve species of the genus Massarina collected from Japan are reported in this article. Among them, 4 new species, M. constricta, M. japonica, M. submediana, and M. uniserialis, are described, illustrated, and compared to similar species. Two species, M. scirpina and M. ryukyuensis, are described as new combination, and 4 species, M. arundinariae, M. fluviatilis, M. peerallyi, and M. rubi, are reported from Japan for the first time. One bambusicolous species, Metasphaeria tuberculosa, is considered to be a synonym of Massarina bambusina.
Received: December 13, 2002 / Accepted: February 6, 2003
Acknowledgments We are grateful to Dr. Shuhei Tanaka, curator of YAM (Yamaguchi University), for the loan of specimens for this study. 相似文献
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Summary. 2H-Pyran-2-ones 1 were transformed with various hydrazines into (E)- or (Z)-α,β-didehydro-α-amino acid (DDAA) derivatives 4 (and 7) containing a highly substituted pyrazolyl moiety attached at the β-position. With heterocyclic hydrazines, the products 4 were accompanied also by decarboxylated enamines E-6. In order to separate (E/Z)-mixtures of acids, they were transformed to the corresponding methyl esters 9 and 10 by the application of diazomethane. Catalytic hydrogenation under high pressures with Pd/C as a catalyst resulted in the formation
of racemic alanine derivatives 11.
Received January 29, 2002 Accepted May 27, 2002 Published online December 18, 2002
RID="*"
ID="*" Dedicated with deep respect to Professor Waldemar Adam on the occasion of his 65th birthday.
Acknowledgements We thank the Ministry of Education, Science and Sport of the Republic of Slovenia for the financial support (P0-0503-103).
Dr. B. Kralj and Dr. D. Žigon (Center for Mass Spectroscopy, “Jožef Stefan” Institute, Ljubljana, Slovenia) are gratefully
acknowledged for the mass measurements.
Authors' address: Prof. Marijan Kočevar, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, SI-1000 Ljubljana,
Slovenia, E-mail: marijan.kocevar@uni-lj.si 相似文献
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Summary. The 14-residue peptaibol antibiotic trichovirin I 4A of the structure Ac-Aib-L-Asn-L-Leu-Aib-L-Pro-L-Ala-L-Val-Aib-L-Pro-Aib-L-Leu-Aib-L-Pro-L-Leuol
(Aib = α-aminoisobutyric acid, Leuol = leucinol) was synthesized by stepwise conventional solution phase synthesis using the Z/OtBu(OMe) strategy and HOBt/EDC as coupling reagents. Intermediates were fully characterized and the identity of the synthetic
peptide with the component 4A of the natural, microheterogeneous peptide mixture was proven by electrospray mass spectrometry,
HPLC, and bioassay.
Received March 25, 2002 Accepted June 14, 2002 Published online December 18, 2002
RID="*"
ID="*" Dedicated to Prof. Dr. Günther Jung. Tübingen University, on the occasion of his 65th anniversary.
Authors' address: Prof. Dr. Hans Brückner, Interdisciplinary Research Center, Institute of Nutritional Science, Department of Food Sciences,
Justus-Liebig-University of Giessen, Heinrich-Buff-Ring 26, D-35392 Giessen, Germany, Fax: +49-641-99-39149, E-mail: hans.brueckner@ernaehrung.uni-giessen.de
Abbreviations: Amino acids are abbreviated according to three-letter-nomenclature; Aib, α-aminoisobutyric acid (2-methylalanine); Iva (isovaline, 2-ethylalanine); Leuol, L-leucinol [(S)-2-amino-4-methyl-1-pentanol]; AAA, amino acid analysis; EI-MS, electron impact mass spectrometry; ESI-MS, electrospray ionization
mass spectrometry; HPLC, high performance liquid chromatography; Z, benzyloxycarbonyl; Fmoc, 9-fluorenylmethyoxycarbonyl;
OtBu, tertiary butoxy (tert-butylester); OMe, methoxy (methyl ester); OBzl, benzyloxy (benzyl ester); TDM, N,N,N′,N′-tetramethyl-4,4′-diamino-diphenylmethane
(Arnold's base); for other abbreviations see Experimental. 相似文献