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1.
Based on the study of the neotype and the astogeny of the type specimens of the species Ascopora nodosa (Fischer von Waldheim, 1837), the diagnosis and species composition of the genus Ascopora Trautschold, 1876 are emended. The genus Ascopora and three species out of the five included in this genus—A. nodosa (Fischer von Waldheim, 1837); A. sokolovae Schulga-Nesterenko, 1955; and A. latiaxis Schulga-Nesterenko, 1955—are described. A new genus, Tetrasella gen. nov., with the type species T. blanda sp. nov. is described. This genus comprises five species, transferred from the composition of the genus Ascopora. An emended diagnosis of the genus Ascoporella Krutchinina, 1986, is provided. This genus comprises nine species, of which two, A. lecta sp. nov. and A. mera sp. nov., are described as new species.  相似文献   

2.
The Ganitrus group of Elaeocarpus L. (incl. Elaeocarpus Sect. Ptilanthus Schltr.) as found in Malesia is examined and some understanding reached. The group is more complex and speciose in eastern Malesia, especially in Papuasia (with the Philippines, Sulawesi and Maluku somewhat less rich) than in western and central Malesia. E. angustifolius Blume (syn. E. ganitrus & E. sphaericus auctt. mult.) — the source of the ornamental beads known as rudraksha of eastern commerce, from which malas or rosaries are made — is considered to be very variable in Malesia and probably varies further in the extremes of its range; outside Malesia the Ganitrus group is represented by ‘E. angustifolius s.l.’ only. The following species are recognised: E. altisectus Schltr. with a new subsp. carrii Coode from New Guinea; E. angustifolius Blume; E. avium Coode sp. nov. from New Guinea; E. buderi Coode; E. dolichostylus Schltr. with E. chloranthus treated as var. chloranthus (A. C. Sm.) Coode from New Guinea, with a new var. elliptifolius Coode from the Talaud/Sangihe Is. and a new var. hentyi Coode (replacing and re-interpreting subsp. collinus Coode) from New Guinea; E. fulvus Elmer; E. kaniensis Schltr.; E. ornatus Coode sp. nov. from New Guinea; E. osiae Coode sp. nov. from Bougainville I.; E. ptilanthus Schltr.; E. ramiflorus Merr. and E. trichopetalus Merr. & Quisumb. — a total of 12 species although the last two are perhaps not truly distinct from E. angustifolius. The stone sculpturing is discussed and some useful characters revealed. Attention is drawn to a collection from mid-altitude in Papua New Guinea, inadequately known but probably a new species in this group.  相似文献   

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4.
Robinia pseudoacacia microsymbionts from plants growing in Poland and Japan were evaluated for phylogeny and taxonomic position by genomic approach. Based on the comparative analyses of atpD (368 bp) and dnaK (573 bp) gene sequences as well as 16S rDNA restriction analysis (RFLP-16S rDNA), R. pseudoacacia microsymbionts were identified as Mesorhizobium strains. In dnaK and atpD gene phylograms R. pseudoacacia nodulators formed robust, monophyletic clusters with Mesorhizobium species with the nucleotide sequence similarity of 91–98% and 90–98%, respectively. The classification of R. pseudoacacia rhizobia to the genus Mesorhizobium was also supported by amplified 16S rDNA restriction analysis. The studied bacteria formed common clusters with Mesorhizobium species, and their DNA patterns were identical or nearly identical to Mesorhizobium genus strains. When DNA-DNA hybridization was performed, the total DNA of the representative R. pseudoacacia rhizobia exhibited 51–75% relatedness to DNA of Mesorhizobium amorphae ICMP15022 strain and below 41% to DNA of other Mesorhizobium species. These results showed that R. pseudoacacia and M. amorphae belong to the same genomospecies. The G+C content of DNA of R. pseudoacacia two microsymbionts was 59.7 and 60.6 mol% compared to 61–64 mol% across M. amorphae strains.  相似文献   

5.
In this work, the variability of spo0A gene in the genus Geobacillus and applicability of this gene for the taxonomy within this genus were evaluated. The protein Spo0A is the master regulator of the endospore-forming process in the all endospore-forming bacteria. Geobacillus genus-specific primers GEOSPO were designed based on the sequences of Geobacillus spo0A gene available through the public databases. Inter and intraspecific variability of Geobacillus spo0A gene was determined after sequencing of the GEOSPO-PCR products. Geobacillus spo0A sequence analysis showed that three species—Geobacillus thermodenitrificans, G. stearothermophilus, and G. jurassicus—could be easily identified. Similarity between the sequences of these species and the other species were in the range of 83.3%–92.0%. In contrast, intraspecific similarity of G. thermodenitrificans and G. stearothermophilus was high—above 99.0%. Similarity of spo0A sequences of G. subterraneus–G. uzenensis species cluster also matched this interval. Intercluster similarity between G. lituanicus–G. thermoleovorans–G. kaustophilus–G. vulcani and G. thermocatenulatus–G. gargensisG. caldoxylosilyticus–G. toebii–G. thermoglucosidasius species clusters, as well as interspecific similarity within these two clusters was in the range of the intraspecific similarity determined for G. thermodenitrificans and G. stearothermophilus. It was also determined that spo0A cannot be used as the phylogenetic marker for the genus Geobacillus.  相似文献   

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7.
On the family Brassicaceae, the causal agent responsible for downy mildew disease was originally regarded as a single species, Peronospora parasitica (now under Hyaloperonospora), but it was recently reconsidered to consist of many distinct species. In this study, 11 specimens of Peronospora drabae and P. norvegica parasitic on the genus Draba were investigated morphologically and molecularly. Pronounced differences in conidial sizes (P. drabae: 14–20 × 12.5–15.5 μm; P. norvegica: 20–29 × 15.5–22 μm) and 7.8% sequence distance between their ITS1-5.8S-ITS2 rDNA sequences confirmed their status as distinct species. Based on ITS phylogeny and morphology (monopodially branching conidiophores, flexuous to sigmoid ultimate branchlets, hyaline conidia and lobate haustoria), the two species unequivocally belong to the genus Hyaloperonospora and not to Peronospora to which they were previously assigned. Therefore, two new combinations, Hyaloperonospora drabae and H. norvegica, are proposed. The two taxa are illustrated and compared using the type specimen for H. norvegica and authentic specimens for H. drabae, which is lectotypified.  相似文献   

8.
 A new species of Erysiphe sect. Uncinula is described and illustrated from Patagonia, Argentina. Erysiphe patagoniaca sp. nov., found on leaves of Nothofagus × antarctica, is similar to E. nothofagi and E. kenjiana, but differs in its appendages being twisted throughout their length and the number of appendages, asci, and ascospores. The two endemic species of Erysiphe sect. Uncinula, E. magellanica and E. nothofagi, coexisted on the same leaves together with Erysiphe patagoniaca. Received: September 19, 2002 / Accepted: November 28, 2002 Acknowledgments The authors are grateful to Ms. Seiko Niinomi for providing the micrographs of ascomata of Erysiphe spp. on Nothofagus. Correspondence to:S. Takamatsu  相似文献   

9.
10.
Partial recN gene sequences (>1 kb) were obtained from 35 type strains of the genus Amycolatopsis. Phylogenetic trees were constructed to determine the effectiveness of using this gene to predict taxonomic relationships within the genus. The use of recN sequence analysis as an alternative to DNA–DNA hybridization (DDH) for distinguishing closely related species was also assessed. The recN based phylogeny mostly confirmed the conventional 16S rRNA and gyrB gene-based phylogenies and thus provides further support for these phylogenetic groupings. As is the case for the gyrB gene, pairwise recN sequence similarities cannot be used to predict the DNA relatedness between type strains but the recN genetic distance can be used as a means to assess quickly whether an isolate is likely to represent a new species in the genus Amycolatopsis. A recN genetic distance of >0.04 between two Amycolatopsis strains is proposed to provide a good indication that they belong to different species (and that polyphasic taxonomic characterization of the unknown strain is worth undertaking).  相似文献   

11.
Haptoglossa spp. (Lagenidiales, Oomycetes) have been known to parasitize microscopic animals by means of a "gun" cell that shoots an infection cell, named the sporidium, into the body of the animal. A thallus grown from the sporidium changes into a zoosporangium at maturation to produce a number of zoospores that encyst after a swarming period, and the resulting cysts germinate to produce gun cells. In Haptoglossa zoospora, endoparasitic in nematodes, the cysts of primary zoospores that swam for about 5 min did not develop gun cells but produced secondary zoospores that swam for about 3 h. After encystment of the secondary zoospores, each secondary cyst germinated to produce a gun cell. In the present study, the secondary zoospores of the genus Haptoglossa could be recorded with a videocassette recorder for the first time. The videocassette recording also revealed the infection of a nematodes by H. zoospora and H. heterospora to be composed of two steps of injection of a sporidium by the gun cell, in which the gun cell came in contact with the cuticle of a nematode and produced a spherical adhesorium on the tip of the cell in 0.07–0.1 s in both species. The adhesorium was ∼2 μm in H. zoospora and ∼4 μm in H. heterospora. When the adhesorium infiated to full size, it shot the sporidium into the nematode's body in 0.5–0.65 s and in 0.2–0.5 (or rarely 1.0) s in H. zoospora and H. heterospora, respectively. After shooting, the empty gun cell with an empty cyst case was separated from the cuticle immediately in both species. Received: October 3, 2001 / Accepted: December 13, 2001  相似文献   

12.
Genome predictions based on selected genes would be a very welcome approach for taxonomic studies. We analyzed three genes, recN, flaA, and ftsY, for determining if these genes are useful tools for systematic analyses in the genus Anoxybacillus. The genes encoding a DNA repair and genetic recombination protein (recN), the flagellin protein (flaA), and GTPase signal docking protein (ftsY) were sequenced for ten Anoxybacillus species. The sequence comparisons revealed that recN sequence similarities range between 61% and 99% in the genus Anoxybacillus. Comparisons to other bacterial recN genes indicated that levels of similarity did not differ from the levels within genus Anoxybacillus. These data showed that recN is not a useful marker for the genus Anoxybacillus. A 550–600-bp region of the flagellin gene was amplified for all Anoxybacillus strains except for Anoxybacillus contaminans. The sequence similarity of flaA gene varies between 61% and 76%. Comparisons to other bacterial flagellin genes obtained from GenBank (Bacillus, Pectinatus, Proteus, and Vibrio) indicated that the levels of similarity were lower (3–42%). Based on these data, we concluded that the variability in this single gene makes it a particularly useful marker. Another housekeeping gene ftsY suggested to reflect the G+C (mol/mol) content of whole genome was analyzed for Anoxybacillus strains. A mean difference of 1.4% was observed between the G+C content of the gene ftsY and the G+C content of the whole genome. These results showed that the gene ftsY can be used to represent whole G+C content of the Anoxybacillus species.  相似文献   

13.
Partial gyrB sequences (>1 kb) were obtained from 34 type strains of the genus Amycolatopsis. Phylogenetic trees were constructed to determine the effectiveness of using this gene to predict taxonomic relationships within the genus. The use of gyrB sequence analysis as an alternative to DNA–DNA hybridization was also assessed for distinguishing closely related species. The gyrB based phylogeny mostly confirmed the conventional 16S rRNA gene-based phylogeny and thus provides additional support for certain of these 16S rRNA gene-based phylogenetic groupings. Although pairwise gyrB sequence similarity cannot be used to predict the DNA relatedness between type strains, the gyrB genetic distance can be used as a means to assess quickly whether an isolate is likely to represent a new species in the genus Amycolatopsis. In particular a genetic distance of >0.02 between two Amycolatopsis strains (based on a 315 bp variable region of the gyrB gene) is proposed to provide a good indication that they belong to different species (and that polyphasic taxonomic characterization of the unknown strain is worth undertaking). Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. The GenBank accession numbers for the gyrB gene sequences obtained in this study are shown in Table 1.  相似文献   

14.
Summary  Eleven species comprising the Madagascan genus Vaughania are subsumed within the large pantropical genus Indigofera. Six new combinations are made; the remaining species were originally described in Indigofera.  相似文献   

15.
The Bacteroides genus, the most prevalent anaerobic bacteria of the intestinal tract, carries a plethora of the mobile elements, such as plasmids and conjugative and mobilizable transposons, which are probably responsible for the spreading of resistance genes. Production of β-lactamases is the most important resistance mechanism including cephalosporin resistance to β-lactam agents in species of the Bacteroides fragilis group. In our previous study, the cfxA gene was detected in B. distasonis species, which encodes a clinically significant broad-spectrum β-lactamase responsible for widespread resistance to cefoxitin and other β-lactams. Such gene has been associated with the mobilizable transposon Tn4555. Therefore, the aim of this study was to detect the association between the cfxA gene and the presence of transposon Tn4555 in 53 Bacteroides strains isolated in Rio de Janeiro, Brazil, by PCR assay. The cfxA gene was detected in 11 strains and the Tn4555 in 15. The transposon sequence revealed similarities of approximately 96% with the B. vulgatus sequence which has been deposited in GenBank. Hybridization assay was performed in attempt to detect the cfxA gene in the transposon. It was possible to associate the cfxA gene in 11 of 15 strains that harbored Tn4555. Among such strains, 9 presented the cfxA gene as well as Tn4555, but in 2 strains the cfxA gene was not detected by PCR assay. Our results confirm the involvement of Tn4555 in spreading the cfxA gene in Bacteroides species.  相似文献   

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17.
The very common and species-rich Scleractinian genus Actinastrea (family Actinastraeidae, suborder Archeocaeniina) is revised on the basis of the type material of its type species and additional material from the type locality. A lectotype is designated for the type species. It was discovered that Jurassic to Early Cretaceous corals currently assigned to Actinastrea do not fit into the concept of this genus. These species belong to the genus Stelidioseris, which is also revised on the basis of the type of the type species, including designating a lectotype. These two genera are distinguished by various characteristics: septal external parts are swollen in Actinastrea but not in Stelidioseris, the costae are confluent in Stelidioseris but not in Actinastrea, the coenosteum is granulated in Actinastrea but narrow than in Actinastrea and only with costae in Stelidioseris. Actinastrea is restricted to the Late Cretaceous (Late Turonian—Maastrichtian), whereas Stelidioseris originates in the Jurassic and reaches into the Late Cretaceous, but is less common from the Turonian on.  相似文献   

18.
The primary structures of the genes encoding the β-subunits of a type II topoisomerase (gyrase, gyrB) and a type IV topoisomerase (parE) were determined for 15 strains of thermophilic bacteria of the genus Geobacillus. The obtained sequences were used for analysis of the phylogenetic similarity between members of this genus. Comparison of the phylogenetic trees of geobacilli constructed on the basis of the 16S rRNA, gyrB, and parE gene sequences demonstrated that the level of genetic distance between the sequences of the genes encoding the β-subunits of type II topoisomerases significantly exceeded the values obtained by comparative analysis of the 16S rRNA gene sequences of Geobacillus strains. It was shown that, unlike the 16S rRNA gene analysis, comparative analysis of the gyrB and parE gene sequences provided a more precise determination of the phylogenetic position of bacteria at the species level. The data obtained suggest the possibility of using the genes encoding the β-subunits of type II topoisomerases as phylogenetic markers for determination of the species structure of geobacilli.  相似文献   

19.
A bacterial strain, designated KMM 6244T, was isolated from the sea urchin Strongylocentrotus intermedius and subjected to a polyphasic taxonomic investigation. The bacterium was found to be heterotrophic, aerobic, non-motile and spore-forming. Comparative phylogenetic analysis based on 16S rRNA gene sequencing placed the marine isolate in the genus Bacillus. The nearest neighbor of strain KMM 6244T was Bacillus decolorationis LMG 19507T with a 16S rRNA gene sequence similarity of 98.0%. Sequence similarities with the other recognized Bacillus species were less than 96.0%. The results of the DNA–DNA hybridization experiments revealed a low relatedness (37%) of the novel isolate with the type strain of B. decolorationis LMG 19507T. Strain KMM 6244T grew at 4–45°C and with 0–12% NaCl. It produced catalase and oxidase and hydrolyzed aesculin, casein, gelatin and DNA. The predominant fatty acids were anteiso-C15:0, iso-C15:0, anteiso-C17:0, C15:0, iso-C16:0 and iso-C14:0. The DNA G + C content was 39.4 mol%. A combination of phylogenetic, genotypic and phenotypic data clearly indicated that strain KMM 6244T represents a novel species in the genus Bacillus, for which the name Bacillus berkeleyi sp. nov. is proposed. The type strain is KMM 6244T (KCTC 12718T = LMG 26357T).  相似文献   

20.
Members of the yeast genus Malassezia, including atypical strains, are lipophilic except for Malassezia pachydermatis. New physiological features that characterize atypical Malassezia strains are mainly associated with alteration in Tween assimilation pattern — such isolates still require lipids for growth. We isolated three non-lipid-dependent strains of Malassezia from patients with diagnosed atopic dermatitis (AD). These isolates could not be identified to the species level via their physiological properties. Phylogenetic trees, based on the D1/D2 regions of the 26S rDNA gene sequences and nucleotide sequences of the ITS1-5.8S-ITS2 rRNA region, showed the isolates to belong to Malassezia furfur. Three non-lipid dependent isolates from AD skin were conspecific, and sequences analysis proved them to be M. furfur.  相似文献   

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