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1.
  1. The main pathway of the anaerobic metabolism of l-malate in Saccharomyces bailii is catalyzed by a l-malic enzyme.
  2. The enzyme was purified more than 300-fold. During the purification procedure fumarase and pyruvate decarboxylase were removed completely, and malate dehydrogenase and oxalacetate decarboxylase were removed to a very large extent.
  3. Manganese ions are not required for the reaction of malic enzyme of Saccharomyces bailii, but the activity of the enzyme is increased by manganese.
  4. The reaction of l-malic enzyme proceeds with the coenzymes NAD and (to a lesser extent) NADP.
  5. The K m-values of the malic enzyme of Saccharomyces bailii were 10 mM for l-malate and 0.1 mM for NAD.
  6. A model based on the activity and substrate affinity of malic enzyme, the intracellular concentration of malate and phosphate, and its action on fumarase, is proposed to explain the complete anaerobic degradation of malate in Saccharomyces bailii as compared with the partial decomposition of malate in Saccharomyces cerevisiae.
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2.
Previous studies proposed the involvement of theN-methyl-D-aspartate (NMDA) type of glutamate receptors in the development of sensitization to the convulsive effect of cocaine (cocaine kindling). The present study was undertaken to determine, first, if cocaine kindling is associated with enhanced sensitivity of the NMDA receptor to the convulsive response ofN-methyl-D,L-aspartate (NMDLA), and second, whether in vivo modulation of nitric oxide synthase (NOS) function regulates the development of cocaine kindling. The following results were observed:
  1. Cocaine-kindled animals were significantly more susceptible to the convulsive effect of the NMDA receptor agonist NMDLA than saline controls;
  2. Pretreatment with the NOS inhibitor NG-nitro-L-arginine methyl ester (L-NAME; 100 mg/kg; ip) blocked the development of cocaine kindling;
  3. The protective effect of L-NAME was partially reversed with the coadministration of the NOS substrate,L-arginine (300 mg/kg; ip), but notD-arginine; and
  4. L-Arginine (300 mg/kg; ip), but notD-arginine, amplified the development of cocaine kindling. Taken together, these findings suggest that supersensitivity of the NMDA receptor and activation of NOS may underlie the development of cocaine kindling.
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3.
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   

4.
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   

5.
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   

6.
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   

7.
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   

8.
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   

9.
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   

10.
Die siebente Studie aus der Serie der vorbereiteten Studien über die SubfamilieJungermannioideae (Jungermanniaceae, Hepaticae) enthält die taxonomische Bearbeitung des Subg.Plectocolea (Mitt.) Amak. (GattungJungermannia L. emend.Dum.) in Europa (inkl. Kleinasien) und Bemerkungen zu den nordamerikanischen Arten, die eingehend vonSchuster (1969) bearbeitet wurden. Im genannten Gebiet kommen 8 Arten vor, u. zw.J. crenuliformis Aust.,J. evansii nom. nov.,J. fossombronioides Aust.,J. hyalina Lyell inHook.,J. obovata Nees,J. paroica (Schifen.) Grolle,J. subelliptica (Lindb. exKaal.) Lev. undJ. subtilissima (Schiffn.) Grolle. Alle Arten gehören zu der SektionChascostoma (Lindb.) Váňa.  相似文献   

11.
Up-to-date results of taxonomic and phytogeographic studies ofOenothera subsect.Oenothera in the eastern part of the Czech Republic (Moravia and Silesia) are presented. A new hybridogenous species,Oe. moravica Jehlík etRostański (=Oe. fallax × Oe. victorini), is described from S Moravia. Several taxa and hybrids are reported for the first time for the Czech Republic:Oe. victorini Gates etCatcheside (=Oe. rostanskii Jehlík),Oe. × wienii Renner exRostański,Oe. acutifolia × Oe. victorini. Other taxa are recorded from the eastern part of the Czech Republic for the first time:Oe. acutifolia Rostański,Oe. hoelscheri Renner exRostański,Oe. parviflora L.,Oe. subterminalis Gates. The taxonomy ofOe. pycnocarpa Atkinson etBartlett is discussed. A survey of species and hybrids ofOenothera subsect.Oenothera in the Czech Republic is added.  相似文献   

12.
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   

13.
Die vorliegende Studie, die erste aus der Serie der vorbereiteten Studien über dieJungermannioideae (Jungermanniaceae, Hepaticae), enthält den allgemeinen Teil (Material, historische Übersicht, morphologische Charakteristik, verwandtschaftliche Beziehungen, phytogeographische Charakteristik), sowie Bemerkungen zu den monotypischen Gattungen dieser Subfamilie (Cryptocolea Schust.,Cryptocoleopsis Amak.,Diplocolea Amak.,Horikawaella Hatt. etAmak.,Scaphopyllum Inoue und auchHattoria Schust. mit unsicherer taxonomischer Stellung). Ausser den 6 obenerwähnten monotypischen Gattungen stellte der Verfasser noch zwei andere Gattungen zu denJungermannioideae, u. zw.Jungermannia L. emend.Dum. undNardia S. Gray corr.Carring. Diese Gattungen sind in der vorliegenden Studie allgemein charakterisiert; ihre Arten werden in den folgenden Studien behandelt.  相似文献   

14.
15.
Die vorliegende Studie, die letzte aus der Serie der vorbereiteten, Studien über die SubfamilieJungermannioideue (Jungermanniaceae, Hepaticae) ist den Arten der GattungNardia S. Gray corr.Carring. gewidmet. Die GattungNardia wird in zwei Untergattungen gegliedert, u. zw. Subg.Geoscypharia Trev. mit den Sektionen Sect.Breidlerion Grolle (2 Arten), Sect.Flagelliformes Inoue (2 Arten), Sect.Geoscypharia (6 Arten), Sect.Nudae sect. nova (1 Art) und Sect.Subclavatae Inoue (3 Arten) und Subg.Nardia (1 Art). Von 16 bekannten Arten der Gattung (eine Art, die nur im sterilen Zustand bekannt ist, hat eine unsichere Stellung) sind in dieser Studie 8 Arten (N. breidleri (Limpr.) Lindb.,N. geoscyphus (De Not.) Lindb.,N. insecta Lindb.,N. scalaris S. Gray corr. Trev.,N. nuda (Lindenb. etGott.)Váňa,N. assamica (Mitt.) Amak.,N. succulenta (Rich. exLehm.)Spruce undN. compressa (Hook.) S. Gray corr. Trev.) eingehend taxonomisch bearbeitet. Die verbliebenen 8 Arten wurden schon von anderen Autoren (Amakawa, Grolle, Inoue, Schuster) oder vom Verfasser in früheren Studien bearbeitet.  相似文献   

16.
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   

17.
18.
The present paper deals with the following three mountainOxytropis species:Oxytropis urumovii Jáv. inUrumov, an endemic species of the Pirin (Bulgaria);O. dinarica (Murb.) Wettst. distributed predominantly in Yugoslavia, andO. campestris which is common in the East Alps, but very rare in the Balkans. Three subspecies ofO. dinarica were distinguished: subsp.dinarica, subsp.weberi Chrtek etChrtková, and subsp.velebitica Chrtek etChrtková. In addition, a new combinationO. halleri Bunge exKoch subsp.korabensis (Kümmerle etJáv.)Chrtek etChrtková is given.  相似文献   

19.
Natural control agents of the satin moth,Leucoma salicis (L.) were examined in 2Populus grandidentata Michaux stands. Highest mortality occurred in overwintering larvae, with the causal agents 2 fungi,Paecilomyces sp. andHirsutella gigantea Petch, a factor causing death symptomatic of a pathogen, the parasiteEupteromalis hemipterus (Walker) and death from unknown causes. Mortality fromPaecilomyces sp. andE. hemipterus was reduced where overwintering sites were covered with burlap cloth. Parasites recovered from larvae and pupae included the braconidsApanteles melanoscelus (Ratzeburg) andMeteorus versicolor (Wesmeal), the ichneumonidCoccygomimus pedalis (Cresson), the tachinidsCompsilura concinnata (Meigen),Carcelia laxifrons Villeneuve,Tachinomyia variata Curran, and the sarcophagidsSarcophaga aldrichi Parker andAgria housei Shewell. Larval and pupal predators included the carabidCalosoma frigidum Kirby, pentatomids, and birds, particularly black-billed cuckoos,Coccyzus erythrophthaimus (Wilson). Eggs were parasitized by the scelionidTelenomus prob.californicus Ashmead and the trichogrammidTrichogramma minutum (Riley). Predators of adult satin moths included the hermit thrush,Hylocichla guttata (Pallas), and pentatomid bugs.  相似文献   

20.
The species of three genera—Sporoschisma Berk. etBr.,Sporoschismopsis Hol.-Jech. etHennebert andCatenularia Grove are treated in this paper from Czechoslovakia:Sporoschisma juvenile Boudier,S. mirabile Berk. etBr.,Sporoschismopsis moravica Hol.-Jech. etHennebert andCatenularia cuneiformis (Richon) Mason. The studied fungi produce the conidia in basipetal succession, endogenously or subendogenously, quite internally in large phialides or only inside open swollen collarettes.  相似文献   

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