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1.
Summary Leifson's findings, that motile, acetate-oxidizing acetic acid bacteria (Acetobacter) have peritrichous flagella, and that motile, non-acetate oxidizing ones (Acetomonas) have polar flagella, of notably short wavelength, are fully confirmed and photographically illustrated. It is not confirmed, however, that the peritrichous flagella ofAcetobacter are always of “orthodox” type with a wavelength of about 2.9 μ, nor that they always tend to be few in number. In one strain ofA. aceti they were numerous, and the wavelength was as short (1.4 μ) as that considered byLeifson to be uniquely confined to the polar flagella ofAcetomonas. Furthermore the polar flagella of the latter genus seem not always to be multitrichous, strains having been found with only a single polar flagellum.  相似文献   

2.
Rocket line immunoelectrophoresis was used to study the taxonomy ofAzotobacter andAzomonas assessed by reaction with antiserum to the AVO2 strain ofAzotobacter. Forty-five cultures, comprising seventeen species in five genera, showed that antigen “β”, like high-titer somatic agglutination, was restricted to all 11 strains ofAzotobacter vinelandii and to one strain which has been namedAzotobacter macrocytogenes (10EM). A thermoresistant antigen (“γ”) was found to be shared by all strains and species ofAzotobacter andAzomonas investigated.  相似文献   

3.
Summary Electron-micrographs ofGluconobacter melanogenus strain AC 8 (formerlyG. liquefaciens), andG. melanogenus strain U 4, have conclusively confirmed the findings ofShimwell andCarr (1959),Stouthamer (1960), andLeifson (private communication), that these strains are not polarly flagellatedAcetomonas orGluconobacter strains, but peritrichously flagellated acetate-oxidisingAcetobacter ones. When transferred to the latter genus all evidence that these two genera are derived from a “common pool of ancestors”, as claimed byDe Ley (1961), disappears.  相似文献   

4.
Ten wild-type strains ofCorynebacterium fascians, which differed in degree of virulence as measured by ability to cause hyperplasias (multiple stems; fasciation) in pea seedlings, were examined for the presence of plasmids. Four strains were highly virulent, three were avirulent, and three were intermediate in virulence. All of these wild-type strains harbored one plasmid each of approximately 78 megadaltons, as estimated from electrophoretic mobilities in agarose gels capable of resolving reference plasmids ranging from 8.8 to 350 Mdal. Restriction endonuclease (EcoRI andBamHI) cleavage patterns of these nominally 78-MdalC. fascians plasmids suggest that the plasmids are not uniformly of high homology, although similar or identical in electrophoretic mobility in the system used. The relationship of the 78-Mdal plasmids to the phytopathogenicity ofC. fascians remains uncertain, although the restriction endonuclease cleavage patterns do indicate that the plasmids from the highly virulent strains are more closely related to the plasmids from the strains intermediate in virulence than they are to the plasmids from the avirulent strains.  相似文献   

5.
Summary In the sera of humans and various animals there are two different non-specific inhibitors (α-and β-inhibitors) which may be specifically abolished by two substances (α-and β-“enzymes”) both present in filtrates ofV. cholerae. This neutralization is necessary for the rapid classifying of influenza virus strains with the aid of the haemagglutination inhibition test. The egg line strains of the A- and A′-groups are only sensitive to β-inhibitor, while the mouse line strains of the same groups are only sensitive to the α-inhibitor. This does not apply to strains of the B group, where mouse as well as egg lines are sensitive to both inhibitors. With the aid of isolated β-inhibitor (easily to be prepared from cattle serum), it is possible to decide in a quick manner whether or not a strain from the A- or A′-group has previously been adapted to the mouse. With the technical assistance of Miss I.de Nooyer and with the financial support provided by the Institute for Preventive Medicine, Leyden; N.V. Philips Roxane, Weesp; the State Department of Science; the Jan Dekker Fund, and the Curacao Fund for Preventive Medicine.  相似文献   

6.
High concentration of inorganic phosphate in the culture medium ofAspergillus fumigatus inhibited ergot alkaloid synthesis. Addition ofl-tryptophan but not mevalonate or 5-methyltryptophan to the above culture restored the alkaloid synthesis to the level found in normal cultures. The decrease in alkaloid synthesis in the fungus accompanies an increase in cell mass, cellular protein and sterol content. Aspartate aminotransferase and alanine aminotransferase activities were significantly increased in the high-phosphate culture. Part of the work was presented at the seminar on “Enzymatic Methods in Mycology” organised by the Czechoslovak Microbiological Society in Brno, Czechoslovakia, in June 1975.  相似文献   

7.
Earlier studies on Hanuman langurs (Presbytis entellus) around Jodhpur found them entirely vegetarian (Mohnot, 1974;Winkler, 1988). However, recent observations in the open scrub forests of Jodhpur reveal that scale insects may constitute a regular part of their diet and that insectivory is particularly prevalent in the monsoon months July – September. The insect eating in this habitat seems to support the “Energy/nutrient maximization” hypothesis ofHamilton andBusse (1978).  相似文献   

8.
The chemical composition of ethanolic and aqueous extracts from leafy galls produced after infection of Nicotiana tabacum L. plants with Rhodococcus fascians was drastically changed compared to uninfected controls. Chlorogenic acid was abundant both in uninfected and infected plants, but caffeic acid and another cinnamoyl analogue were new in leafy galls. The most pronounced product induced in leafy galls was identified as 7-O-methyl-6-O-β-d-glucopyranosyl coumarin (7-methyl esculin). This is the first report of the presence of this coumarin derivative in tobacco. Interestingly, 7-methyl esculin did not accumulate in the presence of avirulent R. fascians strains nor was it found in leafy galls on other plant species. However, it did appear in crown galls induced by Agrobacterium tumefaciens on tobacco plants. Intriguingly, none of the phenolics known to accumulate in Solanaceae under pathogen attack were found in leafy galls. 7-Methyl esculin barely affected growth of R. fascians nor was it catabolized. Microscopical analysis showed that autofluorescent compounds were located mainly in the abundant meristematic regions of the leafy galls. We postulate that 7-methyl esculin might locally influence plant cell division. Received: 6 March 1996 / Accepted: 30 August 1996  相似文献   

9.
Summary In the investigations described the number of parasites (Trichogramma embryophagum hartig (var.cacoeciae marchal)) released on each tree was determined in relation to the size of the trees. Since the sectional area of the trunks, measured below the ramification, is fairly well correlated with the size of the crowns, we correlated the number ofTrichogramma to the sectional area of the trunks. In 1961 we released a number which generally corresponded to 40 wasps for each square centimeter of the sectional area of the trunks. On the trees of one orchardTrichogramma in larval und pupal stage (in eggs ofSitotroga cerealella (oliv.)) were released in small pipes closed with wiregauze; so big predators could not enter and destroy the unhatchedTrichogramma. An apparatus, named by us “Dosierungs-Trommel” (dose drum) (described and illustrated in the text) makes it possible to spray a definite amount of parasitized and unparasitized eggs (ofAnagasta kuehniella) on the crowns of apple trees. The release ofTrichogramma in this way gave better results than the release of the same amount of wasps from containers fastened to the trunks of apple trees.

Vortrag anl?sslich des Kolloquiums der “Internationalen Arbeitsgruppe für integrierte Sch?dlingsbek?mpfung der C.I.L.B.” — Wageningen (Holland), 5–9 Sept. 1961.  相似文献   

10.
Staphylococcus aureus ssp anaerobius strain S10 was isolated from an outbreak of sheep abscess disease. Sequence of the catalase gene of this strain showed 99 % identity to the catalase gene (katB) sequence of the reference strain (S. aureus ssp. anaerobius strain MVF213) with mismatching of three base pairs. An important substitution located 1036 nucleotides upstream of the initiation codon from “C” in katB to “T” in the catalase gene of strain S10 originated a stop codon. The deduced protein (345 amino acids) is 105 amino acids shorter than that of katB. Partial sequence of the catalase gene of other 8 local isolates in addition to another reference strain (DSM 20714/ATCC 35844) revealed the same mutations in all local (African) strains, whereas the sequence of the reference (European) strain was typical to that of katB. Sequence of the catalase gene of S. aureus ssp. anaerobius strain S10 was deposited in GenBank under accession no. EU281993.  相似文献   

11.
About 1000 bacterial colonies isolated from sea water were screened for their ability to convert dl-5-phenylhydantoin to d(−)N-carbamoylphenylglycine as a criterion for the determination of hydantoinase activity. The strain M-1, out of 11 hydantoinase-producing strains, exhibited the maximum ability to convert dl-5-phenylhydantoin to d(−)N-carbamoylphenylglycine. The strain M-1 appeared to be a halophilic Pseudomonas sp. according to morphological and physiological characteristics. Optimization of the growth parameters revealed that nutrient broth with 2% NaCl was the preferred medium for both biomass and enzyme production. d-Hydantoinase of strain M-1 was not found to be inducible by the addition of uracil, dihydrouracil, β-alanine etc. The optimum temperature for enzyme production was about 25 °C and the organism showed a broad pH optimum (pH 6.5–9.0) for both biomass and hydantoinase production. The organism seems to have a strict requirement of NaCl for both growth and enzyme production. The optimum pH and temperature of enzyme activity were 9–9.5 and 30 °C respectively. The biotransformation under the alkaline conditions allowed the conversion of 80 g l−1 dl-5-phenylhydantoin to 82 g l−1 d(−)N-carbamoylphenylglycine within 24 h with a molar yield of 93%. Received: 15 September 1997 / Received revision: 5 January 1998 / Accepted: 6 January 1998  相似文献   

12.
Production of the exocellular polysaccharide of the phytopathogenic bacteriumXanthomonas fuscans was investigated with respect to its possible use in utilization of industrial wastes containing lactose. Six stablelac + mutants were obtained after the treatment withN-methyl-N′-nitroso-N′-nitroguanidine. The mutants were compared with the parent strain. Morphological and cultivation characteristics, as well as production of the exooellular polysaccharide were compared. The production was found to be maximal during the stationary phase of growth in strains cultivated under submerged conditions. Gas chromatography revealed that the polysaccharide of the parent strain is formed by α- and β-D-glucose and α- and β-d-mannose with a small amount ofd-ribose and 6-deoxy-l-mannose. Composition of the polysaccharides produced by the mutant strains (lac +) does not qualitatively differ from that of the parent strain. However, they were found to contain a higher quantity ofd-mannose, which is favourable for their industrial utilization.  相似文献   

13.
The electrophoretic patterns of 15 protein systems codified for 20 genetic loci were investigated using horizontal electrophoresis. A total of 150 blood samples, from five species of the genusCallithrix were analyzed. Polymorphic variation was observed in 10 out 20 loci analyzed. The genotypic distributions are in Hardy-Weinberg equilibrium. The average heterozygosity (H) varied from 1% to 5%, similar to those observed for other Neotropical primates. The genetic distance coefficients revealed a phylogenetic separation of these species into two groups: (1) “argentata” (C. humeralifer andC. emiliae); (2) “jacchus” (C. jacchus, C. penicillata, andC. geoffroyi). This arrangement is according to the taxonomic arrangement proposed byHershkovitz (1977),de Vivo (1988), andMittermeier et al. (1988). The results in each group are compatible with the subspecies values recorded for the Platyrrhini. These values showed that:C. humeralifer andC. emiliae are subspecies ofC. argentata;C. jacchus, C. penicillata, andC. geoffroyi are subspecies ofC. jacchus. These results also suggest thatC. j. geoffroyi is the “jacchus” group taxon, most similar genetically to the “argentata” group.  相似文献   

14.
The ability ofCarnobacterium spp. originally isolated from vacuum-packed, sugar-salted fish to catabolize arginine was examined. All strains were able to produce citrulline, ornithine, and NH3 from arginine, presumably by the arginine deiminase pathway. The metabolism of arginine was concurrent with acid production from glucose for one strain ofCarnobacterium sp. but delayed for one strain ofCarnobacterium piscicola. The arginine catabolism was not inhibited in the presence of 2% glucose for three strains of carnobacteria during growth in test broth and/or shrimp extract. Growth as well as arginine catabolism was delayed for two strains of carnobacteria by lowering the temperature from 9°C to 4°C. A similar result was obtained by incubating one strain ofC. piscicola in CO2. None of the compoundsl-citrulline,l-ornithine hydrochloride, and (NH4)2SO4 had any effect on growth or arginine catabolism of this strain. Neither did pH of the medium affect the time for initiation of arginine catabolism.  相似文献   

15.
Sixty-two isolates from basidiocarps of Armillaria spp. were obtained from Hokkaido Island, northern Japan. Six species (Armillaria cepistipes, A. gallica, A. nabsnona, A. ostoyae, A. sinapina, and an undescribed species, “Nag. E”) were identified by pairing tests with known tester strains and one subspecies (Armillaria mellea subsp. nipponica, a non-heterothallic form of A. mellea) was identified by its macro- and micro-morphological characters of the basidiocarps. This is the first case of “Nag. E” being reported from Hokkaido Island.  相似文献   

16.
Twenty-two strains ofLemna paucicostata collected from various districts in Japan are classified into 4 types having different morphological features and photoperiodic behaviors. (I) The “N-1” type, widely distributed in north and middle Japan, consists of many short-day strains with similar morphological characteristics. The strain of northern origin, however, has a shorter critical dark period than that of southern origin, and most of the strains flower in response to a single short day though some from middle Japan require 2 short days. (2) The “N-2” type, found in a limited area of northern Japan, is also a short-day type, but has very long critical dark periods and requires 3–5 short-day cycles for flowering. (3) The “S” type, distributed in southern Japan, never flowered in any photoperiod or culture conditions tested. (4) The “K” type, strain 351, collected at the experimental farm of Kyoto University, is a day-neutral type and flowers independently of photoperiod. Application of some SH inhibitors, tungstate or EDTA, or exposure to blue, far-red or low-intensity light caused daylength-independent flowering in short-day strain 6746 (California origin), but none of these treatments caused flowering in any short-day strain collected in Japan.  相似文献   

17.
The nitrogen requirements of 96Gluconobacter, 55Acetobacter and 7Frateuria strains were examined. Only someFrateuria strains were able to grow on 0.5% yeast extract broth or 0.5% peptone broth. In the presence ofd-glucose ord-mannitol as a carbon source, ammonium was used as the sole source of nitrogen by all three genera. With ethanol, only a fewAcetobacter strains grew on ammonium as a sole nitrogen source. Singlel-amino acids cannot serve as a sole source of carbon and nitrogen for growth ofGluconobacter, Acetobacter orFrateuria. The singlel-amino acids which were used by most strains as a sole nitrogen source for growth are: asparagine, aspartic acid, glutamine, glutamic acid, proline and alanine. SomeAcetobacter andGluconobacter strains deaminated alanine, asparagine, glutamic acid, threonine, serine and proline. NoFrateuria strain was able to develop on cysteine, glycine, threonine or tryptophan as a sole source of nitrogen for growth. An inhibitory effect of valine may explain the absence of growth on this amino acid. No amino acid is “essential” forGluconobacter, Acetobacter orFrateuria.  相似文献   

18.
To reduce the volume of seaweed wastes and extract polysaccharides, seaweed-degrading bacteria were isolated from drifting macroalgae harvested along the coast of Toyama Bay, Japan. Sixty-four bacterial isolates were capable of degrading “Wakame” (Undaria pinnatifida) thallus fragments into single cell detritus (SCD) particles. Amongst these, strain 6532A was the most active degrader of thallus fragments, and was capable of degrading thallus fragments to SCD particles within a day. Although the sequence similarity of the 16S rRNA gene of strain 6532A was 100% similar to that of Microbulbifer elongatus JAMB-A7, several distinct differences were observed between strains, including motility, morphology, and utilization of d-arabinose and gelatin. Consequently, strain 6532A was classified as a new Microbulbifer strain, and was designated Microbulbifer sp. 6532A. Strain 6532A was capable of degrading both alginate and cellulose in the culture medium, zymogram analysis of which revealed the presence of multiple alginate lyases and cellulases. To the best of our knowledge, this is the first study to directly demonstrate the existence of these enzymes in Microbulbifer species. Shotgun cloning and sequencing of the alginate lyase gene in 6532A revealed a 1,074-bp open reading frame, which was designated algMsp. The reading frame encoded a PL family seven enzyme composed of 358 amino acids (38,181 Da). With a similarity of 74.2%, the deduced amino acid sequence was most similar to a Saccharophagus enzyme (alg 7C). These findings suggest that algMsp in strain 6532A is a novel alginate lyase gene.  相似文献   

19.
The taxonomy and phylogenetic affinities of the putative “New World vulture”Eocathartes robustus,Lambrecht, 1935 and the “hornbill”Geiseloceros robustus Lambrecht, 1935 from the Middle Eocene of the Geisel Valley in Germany are revised. It is shown that the holotype specimens belong to a single individual, whose osteology closely resembles that ofStrigogyps sapea (Peters, 1987) from the Middle Eocene of Messel (Germany). The species is classified intoStrigogyps robustus (Lambrecht, 1935), n. comb., and provides further evidence for the great similarity between the Eocene avifaunas of the Geisel Valley and Messel.Strigogyps is a representative of the Ameghinornithidae whose phylogenetic affinities are uncertain; there is no fossil record of either Cathartidae (New World vultures) or Bucerotidae (hornbills) from the Geisel Valley.  相似文献   

20.
Total DNA of virulent and avirulent strains of Rhodococcus fascians was resolved by pulsed-field gel electrophoresis (PFGE) into a discrete number of fragments by digestion with the endonucleases AseI and DraI. Restriction endonucleases PacI, PmeI, and SwaI yielded no fragments upon digestion of R. fascians genome, and all the other tested endonucleases recognizing 6 bp released too many fragments. The genome size was 5.6 megabases for the type strain R. fascians DSM 20669, and 5.8 megabases for the virulent R. fascians D188 strain. However the genome size of R. fascians CECT 3001 (NRRL B15096) was 8.0 megabases. No linear chromosome in the megabase range was observed under pulse conditions in which Saccharomyces cerevisiae and Schizosaccharomyces pombe chromosomes were perfectly resolved, suggesting that the R. fascians chromosome is circular. A new linear plasmid pIRN640 of 640 kb was found in the avirulent R. fascians CECT 3001 that did not hybridize with a probe internal to the fas region of pFiD188 known to be involved in plant pathogenicity in the virulent strain R. fascians D188. Virulence was correlated in all strains tested with the presence of the fas region. The AseI and DraI bands corresponding to the extrachromosomal elements were identified providing the basis for a physical map of this organism. Received: 10 October 1997 / Accepted: 28 November 1997  相似文献   

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