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1.
The configuration of quinone systems, cellular fatty acids and diaminopimelic acids in 11 species of thermophilic clostridia which have been classified into new genera based on their 16S rRNA sequences was determined. It was found that menaquinone 7 was present in 10 species as the major component of menaquinone systems by analyses using HPLC with photodiode-array detector and electron impact mass spectrometry. In seven of the 11 species, the major cellular fatty acids were determined to be iso-15:0 and iso-17:0. As a results of chemotaxonomic studies it was demonstrated that the representatives of the new genera Thermoanaerobacter and Thermoanaerobacterium were heterogeneous in their chemical composition, whereas strains of the new genus Moorella and of the new unnamed genus which is composed of (Clostridium) stercorarium and (Clostridium) thermolacticum showed homogeneity in their chemotaxonomic characteristics.  相似文献   

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New species ofCrucianella (1),Asperula (2),Galium (3), and a new subspcies (Galium), most of them endemic to Iraq, are described and their closest affinities discussed. A number of new combinations and status alterations withinCrucianella, Asperula, Galium andCruciata are also published.  相似文献   

4.
The article describes part of the Entactinaria radiolarians from a very rich and well-preserved radiolarian assemblage extracted from a lower Tithonian sample (Mue 22) collected from the Mühlheim Member of the Mörnsheim Formation of southern Germany. With a single exception (genus Odoghertites nov. gen.), all other Entactinaria described are of primitive type, that is their initial spicules are not differentiated into an apical and a basal group and are not connected by arches to form a heteropolar “microsphere”. They have been assigned to five families, four of which are new (Isometractiniidae, Triumbraculidae, Hollandocachoniidae, Odoghertitidae), 10 new genera (Isometractinia, Triumbraculum, Tardentactinia, Lententactinia, Hollandocachonia, Sphaerentofurca, Stylentofurca, Zuegelifurca, Spongentofurca, Odoghertites), and 19 new species. One of the new species comes from the lower Bajocian of Oregon. A new skeletal structural term, support structure, is introduced as a special type of connection between the primary spines and the macrosphere or cortical shell.  相似文献   

5.
Phytochemical investigation of the aerial parts of Lysimachia clethroides led to the isolation of a new acylated flavonol glycoside (1) and a new δ-truxinate derivative (2), together with three known acylated flavonol glycosides. The structures of the new compounds were determined by spectroscopic methods and chemical evidence as quercetin-3-O-β-d-(6-O-Z-p-coumaroyl)glucopyranoside (1) and monomethyl 3,3′,4,4′-tetrahydroxy-δ-truxinate (2), respectively. All of the isolates were evaluated for their in vitro inhibitory activity against aldose reductase.  相似文献   

6.
The increase in prevalence of antimicrobial resistance makes the search for new antibiotic agents imperative. Antimicrobial peptides (AMPs) from natural resources have been recognized as suitable tools to combat antibiotic-resistant bacteria. The liver fluke Clonorchis sinensis living in germ-filled environments could be a good source of antimicrobials. Here, we report the use of a rational protocol that combines AMP predictions based on their physicochemical properties and their in vivo stability to discover AMP candidates from the entire genome of C. sinensis. To screen AMP candidates, in silico analyses based on the physicochemical properties of known AMPs, such as length, charge, isoelectric point, and in vitro and in vivo aggregation values were performed. To enhance their in vivo stability, proteins having proteolytic cleavage sites were excluded. As a consequence, four high-activity, highstability peptides were identified. These peptides could be potential starting materials for the development of new AMPs via structural modification and optimization. Thus, this study proposes a refined computational method to develop new AMPs and identifies four AMP candidates, which could serve as templates for further development of peptide antibiotics.  相似文献   

7.
The bacteria in the genus Cellulomonas are known for their ability to degrade plant cell wall biomass. Cellulomonas fimi ATCC 484 and C. flavigena ATCC 482 have been the subject of much research into secreted cellulases and hemicellulases. Recently the genome sequences of both C. fimi ATCC 484 and C. flavigena ATCC 482 were published, and a genome comparison has revealed their full spectrum of possible carbohydrate-active enzymes (CAZymes). Using mass spectrometry, we have compared the proteins secreted by C. fimi and C. flavigena during growth on the soluble cellulose substrate, carboxymethylcellulose (CMC), as well as a soluble xylan fraction. Many known C. fimi CAZymes were detected, which validated our analysis, as were a number of new CAZymes and other proteins that, though identified in the genome, have not previously been observed in the secretome of either organism. Our data also shows that many of these are co-expressed on growth of either CMC or xylan. This analysis provides a new perspective on Cellulomonas enzymes and provides many new CAZyme targets for characterization.  相似文献   

8.
Two new species of Polystachya Hook. are described and illustrated: Polystachya rydingii Baranow & Mytnik occurring from the Democratic Republic of Congo and P. sosefii Baranow & Mytnik from Cameroon. The species belong to the section Polystachya Kraenzl., which is the only pantropical section in the genus. Maps of the distribution for the new species and their closest relatives and a brief discussion with notes on their habitat, ecology, and altitude are provided.  相似文献   

9.
Questions of biogeography of freshwater cyanobacteria and their ability to colonize new areas have been recently discussed in connection with increasing occurrence of some formerly rare morphospecies in temperate zones. Nevertheless, the general knowledge about the distribution of cyanobacterial species is still fragmentary, and any new findings on cyanobacterial biogeography and spread are valuable. In this study, we provide updated information on the occurrence of Anabaena bergii, Raphidiopsis mediterranea, and Sphaerospermopsis aphanizomenoides in the Czech Republic. In addition, more nostocacean morphospecies are newly reported from the Czech Republic (A. fusca, A. tenericaulis, Dolichospermum curvum, D. mucosum, and S. reniformis). All of these morphospecies were characterized from a morphological point of view, and their phylogenetic affiliations were assessed on the basis of their 16S rRNA gene sequences. Based on these results, Anabaena bergii was reclassified into Chrysosporum gen. nov., and D. tenericaule comb. nova was established.  相似文献   

10.
《Geobios》1986,19(3):279-297
The Mont Aimé Formation, of doubtful age, likely paleocene and probably danian, yielded an association of 7 bryozoan species. Two of them are new: Plagioecia bibensis and Beisselina bigeyae. The stratigraphic conclusions are reduced because the other occuring species, among which are of great importance Planicellaria sp. aff. oculata d'Orbigny and Nellia sp. aff. stricta Labracherie, are probably new. The Bryozoans, which lived in an environment with strong terrigenous discharges, resisted to the mud invasion by means of the high number of their avicularia or respectively of the flexibility of their jointed zoaria or of their substratum.  相似文献   

11.
Eight new species of the African Restionaceae (Restionoideae) are described, viz.: Cannomois anfracta, Cannomois arenicola, Cannomois grandis, Nevillea vlokii, Thamnochortus kammanassiae, Willdenowia pilleata, Restio uniflorus and Restio mkambatiae. A key to the species of Cannomois is provided, as well as a table comparing the characters of the three species in Nevillea. For all new species, notes on the affinities of the species and their habitats are provided. Two new combinations, Cannomois primosii (Pillans) H.P. Linder and Cannomois robusta (Kunth) H.P. Linder, are made.  相似文献   

12.
The synthesis of a new series of acyclic triazoloquinoxalinyl C-nucleosides and their transformation to their cyclic analogs are described following protection, activation, and deprotection with subsequent intramolecular nucleophilic substitution protocol. The antibacterial potency of the new compounds was determined using an inhibition zone diameter test. The results show that 3a and 2b exhibit good activity against Escherichiacoli and Candidaalbicans. On the other hand, the cyclic mesylated C-nucleoside 13 showed activity against the Gram-positive bacteria (Staphylococcusaureus) and antifungal activity against C. albicans.  相似文献   

13.
Data regarding helminth communities can provide insights into health, feeding interactions, behaviour and evolution of their host organisms. Penguins (Spheniscidae) are important components of marine food webs and tracking their helminth communities can be indicative of ecosystem health. New Zealand is home to 5 of the world's 19 penguin species and little is known about their gastrointestinal helminths. Here, we provide the first study on the gastrointestinal helminths of little blue penguins from south-eastern South Island, New Zealand. The helminth community consisted of two species of tapeworm; Tetrabothrius lutzi and Tetrabothrius sp.; three nematode species, Contracaecum eudyptulae, Capillaria sp. and Stegophorus macronectes; two acanthocephalans, Andracantha sigma and Bolbosoma balaenae; and one trematode, Galactosomum otepotiense. The most prevalent parasites were T. lutzi, A. sigma, and C. eudyptulae. This work includes three new host records and five new geographic records. This is the first report of B. balaenae occurring in a host other than a marine mammal. This study adds to our knowledge about the helminth community of New Zealand little blue penguins, and includes new genetic data on helminth species, providing a baseline against which future studies may be compared.  相似文献   

14.
The millipede genus Kronopolites currently comprises 11 species, including a new species from northern Laos: Kronopolites lunatus sp. n. The generic diagnosis is updated, a key given to all known species, and their distributions are mapped.  相似文献   

15.
A new subspecies ofCardamine pratensis L. subsp.major Tom?ovic, and a new hybridCardamine × smejkalii Tom?ovic from theCardamine pratensis complex are described. Both new taxa are defined morphologically, karyologically and by their ecological characteristics.  相似文献   

16.
《Mycoscience》2020,61(3):116-121
Five Simplicillium isolates were obtained from foam generated in an aquarium in Minato-ku, Tokyo, Japan. Using a combination of micro-morphological characteristics and multigene (ITS, SSU, LSU, TEF) phylogenics, the isolates were identified as S. subtropicum and a new species which were previously undescribed. Simplicillium spumae, which is a new species, differs from known Simplicillium species in the morphology of their conidia and conidiophores.  相似文献   

17.
Methanotrophic Verrucomicrobia have been found in geothermal environments characterized by high temperatures and low pH values. However, it has recently been hypothesized that methanotrophic Verrucomicrobia could be present under a broader range of environmental conditions. Here we describe the isolation and characterization of three new species of mesophilic acidophilic verrucomicrobial methanotrophs from a volcanic soil in Italy. The three new species showed 97% to 98% 16S rRNA gene identity to each other but were related only distantly (89% to 90% on the 16S rRNA level) to the thermophilic genus Methylacidiphilum. We propose the new genus Methylacidimicrobium, including the novel species Methylacidimicrobium fagopyrum, Methylacidimicrobium tartarophylax, and Methylacidimicrobium cyclopophantes. These mesophilic Methylacidimicrobium spp. were more acid tolerant than their thermophilic relatives; the most tolerant species, M. tartarophylax, still grew at pH 0.5. The variation in growth temperature optima (35 to 44°C) and maximum growth rates (µmax; 0.013 to 0.040 h−1) suggested that all species were adapted to a specific niche within the geothermal environment. All three species grew autotrophically using the Calvin cycle. The cells of all species contained glycogen particles and electron-dense particles in their cytoplasm as visualized by electron microscopy. In addition, the cells of one of the species (M. fagopyrum) contained intracytoplasmic membrane stacks. The discovery of these three new species and their growth characteristics expands the known diversity of verrucomicrobial methanotrophs and shows that they are present in many more ecosystems than previously assumed.  相似文献   

18.
Perrottetianal A and perrottetianal B, two new diterpene dialdehydes and a new ent-labdane-type diterpene diol have been isolated from the liverwort Porella perrottetiana and their structures have been elucidated by the chemical and spectral evidence.  相似文献   

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The investigation of the aerial parts of V. occidentalis affords six new sesquiterpenes their structures being elucidated by spectroscopic methods. All compounds are derived from muurolene. V. enceloides contains simple compounds, only one being new, which is closely related to a diacetate from Amphiachyris amoenum.  相似文献   

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