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1.
2.
In the years 1976–1981 we studied chromosome counts and karyotypic formulae of the following 29 species of plants from 41 localities (of these 6 from Bohemia, 32 from Moravia, 3 from Slovakia):Batrachium baudotii (Godron) F. W. Schultz,Chenopodium rubrum L.,C. polyspermum L.,C. murale L.,C. ficifolium Sm.,C. opulifolium Schrader ex DC. inLam. et DC.,C. strictum Roth [subsp.strictum, subsp.glaucophyllum (Aellen)Aellen inJust etAellen, subsp.striatiforme Uotila],Arenaria grandiflora L.,Illecebrum verticillatum L.,Spergula morisonii Boreau inDuchartre,Spergularia marginata (DC. inLam. et DC.)Kittel S. marina (L.)Griseb.,S. rubra (L.) J. etC. Presl,Silene conica L.,Sisymbrium loeselii L.,S. volgense Bieb. exE. Fourn.,S. orientale L. [subsp. orientale, subsp.macroloma (A. Pomel)Dvo?ák],S. officinale (L.)Scop.,Descurainia sophia (L.)Webb exPrantl inEngler etPrantl,Nasturtium officinale R. Br. inAiton,Barbarea arcuata (Opiz inPresl J. et C.)Reichenb.,Lunaria annua L.,Soldanella montana Willd.,S. carpatica Vierh. inUrban etGraebner,Lotus tenuis Waldst. etKit. exWilld.,L. uliginosus Schkuhr,Trigonella monspeliaca L.,Geranium sibiricum L.,Lactuca tatarica (L.)C. A. Meyer.  相似文献   

3.
d-Tagatose 3-epimerase family enzymes can efficiently catalyze the epimerization of free keto-sugars, which could be used for d-psicose production from d-fructose. In previous studies, all optimum pH values of these enzymes were found to be alkaline. In this study, a d-psicose 3-epimerase (DPEase) with neutral pH optimum from Clostridium bolteae (ATCC BAA-613) was identified and characterized. The gene encoding the recombinant DPEase was cloned and expressed in Escherichia coli. In order to characterize the catalytic properties, the recombinant DPEase was purified to electrophoretic homogeneity using nickel-affinity chromatography. Ethylenediaminetetraacetic acid was shown to inhibit the enzyme activity completely; therefore, the enzyme was identified as a metalloprotein that exhibited the highest activity in the presence of Co2+. Although the DPEase demonstrated the most activity at a pH ranging from 6.5 to 7.5, it exhibited optimal activity at pH 7.0. The optimal temperature for the recombinant DPEase was 55 °C, and the half-life was 156 min at 55 °C. Using d-psicose as the substrate, the apparent K m, k cat, and catalytic efficiency (k cat/K m) were 27.4 mM, 49 s?1, and 1.78 s?1 mM?1, respectively. Under the optimal conditions, the equilibrium ratio of d-fructose to d-psicose was 69:31. For high production of d-psicose, 216 g/L d-psicose could be produced with 28.8 % turnover yield at pH 6.5 and 55 °C. The recombinant DPEase exhibited weak-acid stability and thermostability and had a high affinity and turnover for the substrate d-fructose, indicating that the enzyme was a potential d-psicose producer for industrial production.  相似文献   

4.
A recombinant l-fucose isomerase from Caldicellulosiruptor saccharolyticus was purified as a single 68 kDa band with an activity of 76 U mg?1. The molecular mass of the native enzyme was 204 kDa as a trimer. The maximum activity for l-fucose isomerization was at pH 7 and 75°C in the presence of 1 mM Mn2+. Its half-life at 70°C was 6.1 h. For aldose substrates, the enzyme displayed activity in decreasing order for l-fucose, with a k cat of 11,910 min?1 and a K m of 140 mM, d-arabinose, d-altrose, and l-galactose. These aldoses were converted to the ketoses l-fuculose, d-ribulose, d-psicose, and l-tagatose, respectively, with 24, 24, 85, 55% conversion yields after 3 h.  相似文献   

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Beet yellows virus (BYV) was mechanically transmitted by sap from sugar-beet plants, infected with BYV, to the plants ofChenopodium quinoa Willd. and ofChenopodium foliosum (Moench) Asch. Mechanical transmission of BYV to the plants ofTetragonia expansa Murr. failed. Infectious material was homogenized in phosphate buffer with veronal and EDTA, pH 7–8. Experimental plants were darkened three days before infection and kept at a temperature of 5°C. Plants ofC. quinoa Willd. were decapitated. Back transmissions fromC. quinoa Willd. andC. foliosum (Moench) Asch. infected with BYV, to sugar-beet plants were carried out by the aveidMyzus persicae Sulz. These transmissions were positive. Filamentous particles of BYV, of an average length 1275 nm, were found in plants ofC. quinoa Willd. andC. Foliosum (Moench) Asch., infected with BYV.  相似文献   

7.
Dersechste Beitrag aus der Serie der vorbereiteten Studien über die SubfamilieJungermannioideae (Jungermanniaceae, Hepaticae) enthält die taxonomische Bearbeitung des Subg.Solenostoma (Mitt.)Amak. (GattungJungermannia L. emend.Dum.) in Europa (inkl. Kaukasus und Kleinasien) und Nordamerika. Im genannten Gebiet kommen 10 Arten vor, u. zw.J. caespiticia Lindenb.,J. caucasica Váňa,J. confertissima Nees,J. gracillima Sm.,J. handelii (Schiffn.)Amak.,J. jenseniana Grolle,J. lignicola (Schiffn.)Grolle,J. pyriflora Steph.,J. rubra Gott. exUnd. undJ. sphaerocarpa Hook. Die ArtJ. confertissima Nees (bisher alsSolenostoma levieri (Steph.)Steph. bezeichnet) gehört zu der SektionDesmorhiza Amak., alle anderen Arten gehören zu der SektionSolenostoma.  相似文献   

8.
The d,d-transpeptidase activity of Penicillin Binding Proteins (PBPs) is essential to maintain cell wall integrity. PBPs catalyze the final step of the peptidoglycan synthesis by forming 4 → 3 cross-links between two peptide stems. Recently, a novel β-lactam resistance mechanism involving l,d-transpeptidases has been identified in Enterococcus faecium and Mycobacterium tuberculosis. In this resistance pathway, the classical 4 → 3 cross-links are replaced by 3 → 3 cross-links, whose formation are catalyzed by the l,d-transpeptidases. To date, only one class of the entire β-lactam family, the carbapenems, is able to inhibit the l,d-transpeptidase activity. Nevertheless, the specificity of this inactivation is still not understood. Hence, the study of this new transpeptidase family is of considerable interest in order to understand the mechanism of the l,d-transpeptidases inhibition by carbapenems. In this context, we present herein the backbone and side-chain 1H, 15N and 13C NMR assignment of the l,d-transpeptidase from Bacillus subtilis (LdtBs) in the apo and in the acylated form with a carbapenem, the imipenem.  相似文献   

9.
Bifidobacterium longum NRRL B-41409 l-arabinose isomerase (l-AI) was overexpressed in Lactococcus lactis using a phosphate depletion inducible expression system. The resting L. lactis cells harboring the B. longum l-AI were used for production of d-tagatose from d-galactose in the presence of borate buffer. Multivariable analysis suggested that high pH, temperature and borate concentration favoured the conversion of d-galactose to d-tagatose. Almost quantitative conversion (92 %) was achieved at 20 g L?1 substrate and at 37.5 °C after 5 days. The d-tagatose production rate of 185 g L?1 day?1 was obtained at 300 g L?1 galactose, at 1.15 M borate, and at 41 °C during 10 days when the production medium was changed every 24 h. There was no significant loss in productivity during ten sequential 24 h batches. The initial d-tagatose production rate was 290 g L?1 day?1 under these conditions.  相似文献   

10.
The present study deals with five genera of hepatics in Africa, Isotachis Mitt., Anastrophyllum (Spruce) Steph., Tritomaria Schiffn. ex Loeske, Gymnocoleopsis (Schust.) Schust. and Lophozia (Dum.) Dum. All African populations of the genus Isotachis Mitt. are considered to be one species, I. aubertii (Schwaegr.) Mitt. Four species of Anastrophyllum (Spruce) Steph. (s.l.), A. auritum (Lehm.) Steph., A. piligerum (Nees) Spruce, A. subcomplicatum (Lehm. et Lindenb.) Steph. and A. minutum (Schreb.) Schust., and two species of Tritomaria Schiffn. et Loeske, T. camerunensis S. Arnell and T. exsecta (Schrad.) Schiffn. ex Loeske occur in Africa. Gymmocoleopsis multiflora (Steph.) Schust. represents a genus and species hitherto unreported for the African flora. Finally, five Lophozia (Dum.) Dum. species, L. argentina (Steph.) Schust., L. capensis S. Arnell, L. decolorans (Limpr.) Steph., L. hedbergii S. Arnell and L. tristaniana (S. Arnell) Váňa, are reported from central and southern Africa; two of these (L. argentina (Steph.) Schust. and L. decolorans (Limpr.) Steph.) represent the first reports from Africa.  相似文献   

11.
D. Blumberg 《BioControl》1973,18(2):125-131
Nine species ofCybocephalus were found in a survey conducted throughout Israel:C. micans (Reitter),C. nigriceps nigriceps (J. Sahiberg),C. nigriceps sinister Endrödy-Younga,C. aegyptiacus Endrödy-Younga,C. mediterraneus Endrödy-Younga,C. pullus Endrödy-Younga,C. fodori minor Endrödy-Younga,C. membranaceus (Reitter) andCybocephalus sp. n.C. micans andC.n. nigriceps are the most prevalent: the former in the Coastal Plain on citrus and the latter in the Arava region on date palms. In most cases the population density of the predator appeared to be related to that of the prey. Armoured scale insects(Homoptera: Diaspididae) were the main prey ofCybocephalus.  相似文献   

12.
Chromosome numbers are reported for 14 species collected in Cuba. The first chromosome records are reported forAlbizzia cubana Britton etWilson (2n=26),Atkinsia cubensis (Britton etWilson)Howard (2n=26),Caesalpinia violacea (Mill.)Standl. (2n=24),Colubrina ferruginosa Brongn. (2n=24). Chromosome numbers of the following species were confirmed:Albizzia lebbeck (L.)Benth. (2n=26),Canavalia maritima (Aubl.)Thouars (2n=22),Casuarina equisetifolia Forst. (2n=18),Cedrela mexicana M.J. Roem. (2n=56),Delonix regia (Bojer)Raf. (2n=28),Guazuma tomentosa H.B.K. (2n=16),Lysiloma bahamense Benth. (2n=26),L. latisiliqua (L.)Benth. (2n=26),Samanea saman (Jacq.)Merrill (2n=26),Thespesia populnea (L.)Soland (2n=26).  相似文献   

13.
Six species of the genusBactrodesmium M. C. Cooke are described in this paper from Czechoslovakia:B. betulicola M.B. Ellis,B. obovatum (Oudemans) M.B. Ellis,B. spilomeum (Berk. etBr.)Mason etHughes including three new speciesB. globosum Hol.-Jech.,B. pyriforme Hol.-Jech. andB. submoniliforme Hol.-Jech.  相似文献   

14.
Three genera of lignicolousHyphomycetes Septonema Corda,Hormiactella Saac. andLylea Morgan-Jones are discussed. Illustrations and determination keys are provided. Five species ofSeptonema—S. fasciculare (Corda) Hughes,S. leptaleum (Ellis & Harkn.) Hughes,S. pinicola Hol.-Jech.,S. secedens Corda andS. laricium Hol.-Jech.—and two species ofHormiactella—H. fusca (Preuss) Sacc. andH. asetosa Hol.-Jech.—have been found in Czechoslovakia. A new speciesS. pseudobinum Hol.-Jech. is described from Romania.Septonema tetracoilum (Corda Hughes is accommodated in the genusLylea Morgan-Jones.  相似文献   

15.
Die achte Studie über die SubfamilieJungermannioideae (Jungermanniaceae, Hepaticae) ist dén Arten der GattungJungermannia L. emend.Dum., die in Australien, Neuseeland und Ozeanien vorkommen, gewidmet. Die meist endemischen Arten, die auf Hawaii vorkommen, werden als eine selbständige (neunte) Studie bearbeitet. Im genannten Gebiet wurden 13 Arten der GattungJungermannia L. emend.Dum. festgestellt.J. (P.) hasskarliana (Nees) Steph.,J. (P.) obliquifolia (Schiffn.) Váňa,J. (P.) tetragona Lindenb.,J. (P.) hirticalyx Steph.,J. (P.) minutiverrucosa Amak.,J. (P.) wattsiana Steph.,J. (S.) ariadne Tayl.,J. (S.) totipapillosa Hodgs.,J. (S.) inundata Hook. fil. etTayl. emend.Mitt. undJ. (S.) orbiculata (Col.) Grolle sind eingehend taxonomisch bearbeitet,J. (P.) micrantha (Mitt.) Steph. wird in die nächste Studie eingereiht.J. (P.) boninensis (Horik.) Inoue wurde vonInoue (Inoue etIwatsuki 1969) eingehend beschrieben und abgebildet,Haplozia comptonii Pears. wurde schon im 2. Teil diskutiert. Die anderen aus dem Gebiet bekannten Arten sind mit den obenerwähnten Arten synonymisiert oder zu anderen Gattungen gestellt.  相似文献   

16.
Die zweite Studie aus der Serie der vorbereiteten Studien über die Subfam.Jungermannioideae (Jungermanniaceae, Hepaticae) enthält eine taxonomische Bearbeitung des Subg.Jungermannia. Nach dem Verfasser gehören zu diesem Subg. nur 7 Arten:J. atrovirens Dum. (identisch mitJ. tristis Nees),J. exsertifolia Steph.,J. gollanii Steph.,J. karl-muelleri Grolle,J. ovato-trigona (Steph. inHerz.) Grolle,J. polaris Lindb. undJ. pumila With. Die anderen, zu diesem Subg. gestellten Arten gehören teilweise zu den anderen Subgenera (J. grossitexta sensuAmak.,J. kuwaharae Amak., undJ. laetevirens (Spruce) K. Müll. inGrolle), teilweise als Synonyma nova zu den obenerwähnten Arten (J. nipponica (Sak. etTakah.) Hatt.,J. tenerrima Steph. (hom. illeg.) undJ. towadensis (Okam.) Hatt., sowie auchJ. tristis Nees).  相似文献   

17.
The taxa very rare in Greece,Gentianella bulgarica (Velen.)J. Holub andPrimula elatior (L.)Hill subsp.intricata (Gren. etGodron)Lüdi Balkan-South Carpathian and mountain subendemic taxon of South and South-Central Europe also the oreophytesGentiana asclepidaea L. andAndrosace villosa L. rare in Greece at high altitudes endemic species of Central Europe and arcto-alpic element both extending South as far as Central Italy and Central Greece as well as the relatively rare species in Greece,Crocus biflorus Mill. which exists in South Europe from Sicily and eastwards and finally four otherIridaceae, i.e.: the South Balkan Asia-Minor subendemic speciesCrocus olivieri Gay andC. pulchellus Herbert, the South Balkan endemic speciesC. veluchensis Herbert and the Mediterranean and mostly East-para-mediterranean subendemic speciesHermodactylus tuberosus (L.)Miller are reported and investigated. However new habitats and records in the Greek area of the investigated species are given, their distribution is discussed, while the existence of the taxa most rare in GreecePrimula elatior (L.)Hill subsp.intricata (Gren. etGodron)Lüdi inHegi,Gentianella bulgarica (Velen.)J. Holub,Gentiana asclepiadea L.,Androsace villosa L. andCrocus biflorus Mill. are presented in the form of a dot map and thus the southernmost limits of their spreading in the Balkan peninsula or in S.E. Europe are elucidated.  相似文献   

18.
Andert’s (1911) inoceramids (Bivalvia) from the topmost Turonian and Lower and lowermost Middle Coniacian (Cretaceous) of the Kreibitz-Zittauer area (Saxony and northern Bohemia) are revised, partially redescribed and newly illustrated. Ten species are discussed. Of the forms described as new byAndert,Inoceramus weiset is shown to represent deformed representatives ofCremnoceramus crassus (Petrascheck), andI. winkholdioides Andert should probably be synonymized withC. brongniarti (Mantell).Andert’s interpretation ofFlegel’s (1904) species, i.e.I. frechi andI. glaziae, is not correct; the former should be referred toMytiloides scupini (Heinz), while the latter includesC. inconstans (Woods),I. vistulensis Walaszczyk,C. rotundatus (Tröger nonFiege), andM. cf.turonicus Walaszczyk. The speciesI. subquadratus Andert representsC. rotundatus (Tröger nonFiege), and hisI. cuvieri var.planus is referred toC. inconstans (Woods) and toC. cf.transilvanicus (Simionescu). The speciesI. protractus Scupin is referred toC. waltersdorfensis (Andert). The main source localities toAndert (1911), i. e. Sonnenberg near Waltersdorf and “Dachsloch” quarry near Innozenzidorf (Czech: Lesne), are of latest Late Turonian/Early Coniacian (theMytiloides scupini andCremnoceramus rotundatus Zones) and late Early Coniacian (C. deformis- C. crassus Zone) age respectively. The third locality, i. e. railway cutting at Tannenberg station (Czech: Jedlová), is probably or late Early Coniacian or early Middle Coniacian age.  相似文献   

19.
It has long been believed that amino acids comprising proteins of all living organisms are only of the l-configuration, except for Gly. However, peptidyl d-amino acids were observed in hydrolysates of soluble high molecular weight fractions extracted from cells or tissues of various organisms. This strongly suggests that significant amounts of d-amino acids are naturally present in usual proteins. Thus we analyzed the d-amino acid contents of His-tag-purified β-galactosidase and human urocortin, which were synthesized by Escherichia coli grown in controlled synthetic media. After acidic hydrolysis for various times at 110°C, samples were derivatized with 4-fluoro-7-nitro-2, 1, 3-benzoxadiazole (NBD-F) and separated on a reverse-phase column followed by a chiral column into d- and l-enantiomers. The contents of d-enantiomers of Ala, Leu, Phe, Val, Asp, and Glu were determined by plotting index d/(d + l) against the incubation time for hydrolysis and extrapolating the linear regression line to 0 h to eliminate the effect of racemization of amino acids during the incubation. Significant contents of d-amino acids were reproducibly detected, the d-amino acid profile being specific to an individual protein. This finding indicated the likelihood that d-amino acids are in fact present in the purified proteins. On the other hand, the d-amino acid contents of proteins were hardly influenced by the addition of d- or l-amino acids to the cultivation medium, whereas intracellular free d-amino acids sensitively varied according to the extracellular conditions. The origin of these d-amino acids detected in proteins was discussed.  相似文献   

20.
On the basis of allozyme and cultivation data, and of additional herbarium material, a taxonomic and nomenclatural revision ofTaraxacum sect.Piesis A.J. Richards exKirschner et?těpánek is provided. The section is made up of halophilous, sexually reproducing taxa. InT. stenocephalum Boiss. etKotschy,T. pindicum Kirschner et?těpánek, sp. nov., andT. perenne Kirschner et?těpánek, sp. nov., a tetraploid chromosome number has been recorded, representing the only known case of sexuality at the tetraploid level in the genus. The complex ofT. stenocephalum, includes some geographically and morphologically extreme populations treated as subspecies: subsp.gumusanicum (Soest)Kirschner et?těpánek, comb. nov., subsp.magnum Kirschner et?těpánek, subsp. nov., and subsp.daralagesicum (Schischk.)Kirschner et?těpánek, comb. nov. In addition toT. bessarabicum (Hornem.)Hand.-Mazz., a widely distributed Eurasian species,T. stenocephalum, a complex centred in Transcaucasia and Anatolia, andT. pachypodum H. Lindb., a North African endemic, four new species are described:T. salsum Kirschner et?těpánek, sp. nov., a diploid endemic confined to E Crimea,T. perenne Kirschner et?těpánek, sp. nov., a tetraploid sexual species known only from SW Crimea,T. pindicum Kirschner et?těpánek, sp. nov., a remarkable tetraploid endemic to the Pindos Mts., Greece, andT. salsitatis Kirschner, ?těpänek etYirdirimli, sp. nov., an Anatolian diploid species. Furthermore, a hybrid betweenT. salsum andT. bessarabicum from Crimea (documented on the basis of allozyme data elsewhere) is given a binomial,T. xmesohalobium Kirschner et?těpánek, nothosp. nov.  相似文献   

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