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1.
J. P. van der Walt 《Antonie van Leeuwenhoek》1965,31(1):341-348
The genusKluyveromyces has been emended to include species forming 1 – 4 crescentiform, reniform, prolate ellipsoidal or spheroidal ascospores.Fourteen species have been assigned to the emended genusKluyveromyces. 相似文献
2.
J. P. Van Der Walt 《Antonie van Leeuwenhoek》1956,22(1):265-272
Summary A new budding yeast has been isolated from soil. Its most striking feature is the formation, generally preceded by isogamous
or heterogamous conjugation, of unusually large multispored asci. The organism possesses a strong fermentative ability, fermenting
glucose, galactose, saccharose and raffinose for one-third. Nitrate is not assimilated. It forms a pellicle in malt extract.
A pseudomycelium is also formed. Cytological examination showed the vegetative cells to be uninucleate. The relationship which
this yeast shows with theDipodascaceae and, in particular, withDipodascus uninucleatus Biggs, is discussed. For the classification of the yeast the new genusKluyveromyces was created. For the species the nameKluyveromyces polysporus is proposed. The Latin diagnosis of both the genus and the species is given. 相似文献
3.
J. P. van der Walt 《Antonie van Leeuwenhoek》1959,25(1):337-343
Summary A new haploid, homothallic yeast isolated from the larval feed ofXylocopa caffra is described.
A study of its properties shows that the evolution of its sexual and biochemical characteristics has not taken place at the
same rate as in the genusHansenula and the proposed genusDekkeromyces. This led the author to the conclusion that in the yeast domain phylogenetic lines may exist in which a unilateral evolution
of biochemical characteristics has taken place.
At least thre groups of yeasts exist where such discrepancies exist between the evolution of their sexual and biochemical
characteristics. The inclusion of the new species in these groups is discussed.
The new species has provisionally been classified in the genusPichia (in sensu Phaff).
A Latin diagnosis of the species is given. 相似文献
4.
W. I. Golubev 《Antonie van Leeuwenhoek》1977,43(3-4):317-322
Ascosporulation in the yeast strain designated asSelenotila intestinalis Krassilnikov was achieved. On the basis of mode of ascus formation and ascospore morphology it is included in the genusMetschnikowia Kamienski as a new species,M. lunata. 相似文献
5.
Genetic studies were employed to rationalize speciation in the yeast genusMetschnikowia. Using haploid cultures derived parasexually or from isolated single ascospores, hybrids were produced between mostMetschnikowia taxa. The results provided strong evidence for the acceptance ofM. bicuspidata as type of the genus, and enabled clarification of the relationships among the recognized species. Speciation was based primarily on ascus and ascospore morphology, as classification based on physiological properties was shown to be ineffective.Metschnikowia bicuspidata var.californica var. nov. is described, and some possible evolutionary trends are discussed.Partial support for J. I. P. from a C.S.I.R.O., Australia, Overseas Postgraduate studentship is gratefully acknowledged. 相似文献
6.
A yeast culture isolated in Japan from soil and invalidly described asKluyveromyces cellobiovorus nom. nud. DBVPG 6286 (CBS 7153) was compared for its physiological and morphological properties and by nDNA-nDNA reassociation experiments with the type strains of several species of the genusKluyveromyces as well as of variousCandida species exhibiting similar phenotypic profiles. DBVPG 6286 was found to be conspecific with the type strain ofCandida intermedia (Ciferri & Ashford) Langeron et Guerra (1938). 相似文献
7.
Stephanus G. Kilian Alje van Deemter Johan L. F. Kock James C. du Preez 《Antonie van Leeuwenhoek》1991,59(3):199-206
The occurrence of proton symport mechanisms for the transport of glucose, galactose, fructose, raffinose and sucrose in 21 yeast strains representing the species of the genusKluyveromyces was surveyed. Proton symport of one or more sugars occurred in 57% of the strains. Similarly, all the sugars investigated were transported by symports by several strains. Symport systems for non-utilisable sugars were rare. Starvation of cells frequently resulted in the appearance of a symport absent in non-starved glucose-grown cells, indicating that repression of proton symports by glucose and subsequent derepression by starvation is a general phenomenon in members ofKluyveromyces. The addition of a sugar to cell suspensions resulted in acidification in 80% of cases, indicating the activity of a membrane-bound ATPase. Acidification was also observed with a number of sugars that cannot be utilised by the particular species. Interesting correlations between the number of proton symports and the abundance of other phenotypic characteristics in members of the genus emerged. Most members of the infertile group of species showing an increase in the number of small chromosomes, inability to produce well-developed pseudomycelium, linoleic and linolenic acid, a decrease in the number of carbon compounds utilised and inability to utilise ethylamine also had no proton symports, whereas most members of the interfertile species produced one or more proton symports. It was concluded that the distribution of the number of proton symports amongstKluyveromyces species coincided with that of other positive characteristics and may therefore be of taxonomic value. 相似文献
8.
The yeast generaEndomyces, Endomycopsella, Guilliermondella andSaccharomycopsis are delimited by the size, structure and pigmentation of the ascospores; they include mycelial yeasts formerly classified
in the invalid genusEndomycopsis. The ultrastructure of the cell wall and the septa of yeasts is briefly discussed. 相似文献
9.
Smith DP Kock JL Motaung MI van Wyk PW Venter P Coetzee DJ Nigam S 《Antonie van Leeuwenhoek》2000,77(4):389-392
Upon cultivation of the yeast Dipodascopsis tothii in its sexual stage, small ascospores are released individually from the ascus tip, which then assemble in sheathed cluster balls. In contrast to Dipodascopsis uninucleata, this yeast produced smooth bean shaped ascospores with sheath-like appendages that assemble in a disordered sheathed ball of ascospores outside the ascus. Strikingly, upon release, the ascus tip contained 3-hydroxy oxylipins, while the released ascospore clusters contained little or no 3-hydroxy oxylipins as indicated by immunofluorescence microscopy. In D. uninucleata, these oxylipins are concentrated on the spore surface and interspore matrix, but not on the ascus tip. 相似文献
10.
Summary Ascospore formation has been observed in three species of the genusBrettanomyces, viz. Brett. bruxellensis. Brett, intermedius andBrett. schanderlii. On media of adequate vitamin content these species form 1–4 hat-shaped ascospores. The spores are liberated rather soon
after maturation. Heat treatment of ascogenous cultures indicated that these species are homothallic.
In view of the fact that ascospore formation has been observed in the type species,Brett. bruxellensis, the transfer of the genus to theEndomycetaceae should be considered.
Part I, II and III: Antonie van Leeuwenhoek 24, 239, 1958;25, 145, 1959;25, 449, 1959. 相似文献
11.
A large number of yeasts were screened for the ability to assimilate hydrocarbons. Not only representatives of the genusCandida, but also species from other perfect and imperfect genera are able to usen-alkanes as sole carbon and energy source. The significance of this feature in yeast systematics is discussed. In general,
all strains of a species share either the ability to assimilate hydrocarbons or the failure to do so. Exceptions are found
in species regarded as heterogeneous, likeCandida sake, Candida diddensii andCandida zeylanoides. In cases where the usual criteria used in identification seem to be inadequate, the simple hydrocarbon assimilation test
may be useful. Also in subgrouping the generaCandida andTorulopsis the test may be of value, because some perfect genera likeHansenula, Kluyveromyces andSaccharomyces lack hydrocarbon-assimilating representatives. 相似文献
12.
Leeuw NJ Swart CW Ncango DM Pohl CH Sebolai OM Strauss CJ Botes PJ van Wyk PW Nigam S Kock JL 《Antonie van Leeuwenhoek》2007,91(4):393-405
Interesting distribution patterns of acetylsalicylic acid (ASA, aspirin) sensitive 3-hydroxy (OH) oxylipins were previously
reported in some representatives of the yeast genus Eremothecium—an important group of plant pathogens. Using immunofluorescence microscopy and 3-OH oxylipin specific antibodies in this
study, we were able to map the presence of these compounds also in other Eremothecium species. In Eremothecium cymbalariae, these oxylipins were found to cover mostly the spiky tips of narrowly triangular ascospores while in Eremothecium gossypii, oxylipins covered the whole spindle-shaped ascospore with terminal appendages. The presence of these oxylipins was confirmed
by chemical analysis. When ASA, a 3-OH oxylipin inhibitor, was added to these yeasts in increasing concentrations, the sexual
stage was found to be the most sensitive. Our results suggest that 3-OH oxylipins, produced by mitochondria through incomplete
β-oxidation, are associated with the development of the sexual stages in both yeasts. Strikingly, preliminary studies on yeast
growth suggest that yeasts, characterized by mainly an aerobic respiration rather than a fermentative pathway, are more sensitive
to ASA than yeasts characterized by both pathways. These data further support the role of mitochondria in sexual as well as
asexual reproduction of yeasts and its role to serve as a target for ASA antifungal action. 相似文献
13.
14.
In the course of a study on yeast diversity in Japan and Thailand, we isolated two yeast strains with bipolar budding patterns.
Physiological and phylogenetic analysis suggested that these two strains were identical to Hanseniaspora
pseudoguilliermondii. However, these strains produced hat-shaped ascospores and endospores, the latter of which was an unknown characteristic
of the species. Endospores were produced on yeast extract–malt extract (YM) plates, though ascospores were produced on cornmeal
agar of H.
pseudoguilliermondii cultures. Endospores were formed in a twin-cell structure composed of a mother cell and a daughter cell, which did not separate
after budding. Unlike the cell wall of the endospores, that of ascospore was stained with a chitin-specific stain. This was
a feature distinguishing endospores and ascospores. Cell morphology of H.
pseudoguilliermondii was compared with other species of the genus by observing their type strains. Other Hanseniaspora species did not show endospore formation under the same condition in which H. pseudoguilliermondii did. Therefore, the formation of endospores was considered to be a species-delimiting character of H. pseudoguilliermondii. 相似文献
15.
One potentially important type of flux from standing-decaying marshgrass is the production and release of ascospores. The
most extensive measurements of ascospore release from the principal marshgrass (Spartina alterniflora, smooth cordgrass) of saltmarshes of the eastern coastal United States involved an arbitrary, weeklong period of wet incubation
of leaf-blade samples. We examined the possibility that shorter incubations would yield higher estimates of hourly rates of
ascospore release, testing wet incubations of 3 to 71 h, using standing-decaying leaf blades of smooth cordgrass from low
on living shoots and high on dead shoots. Incubations of 31 h appeared to be optimal. Species compositions of ascospores expelled
from the two leaf types were distinctly different: high leaves yielded primarily aMycosphaerella species orPhaeosphaeria halima; low leaves yielded primarilyPhaeosphaeria spartinicola or theMycosphaerella species. All of these species consistently exhibited high coefficients of variation (>100%) for their mean rates of release
of ascospores. Only theMycosphaerella species on high leaves gave evidence of a delayed onset of ascospore expulsion during incubation, and this evidence was equivocal.
Grand mean rates of ascospore release forP. spartinicola and theMycosphaerella species were, respectively, 106 and 238 spores cm−2 abaxial leaf area h−1. 相似文献
16.
17.
Maudy Th. Smith C. Shann Wilma H. Batenburg-van der Vegte R. Schmitt E. Wehrli H. J. Roeijmans G. W. van Eijk 《Antonie van Leeuwenhoek》1992,61(4):277-284
The new genusBotryozyma with a single species,B. nematodophila is proposed for two isolates from nematodes (Panagrellus zymosiphilus) occurring in grapes with sour-rot. The new genus has typical ascomycetous characteristics and, being unable to produce ascospores, is placed in the family Candidaceae. 相似文献
18.
Adam Dawidziuk Joanna Kaczmarek Anna Podlesna Idalia Kasprzyk Malgorzata Jedryczka 《Grana》2013,52(3):240-248
Leptosphaeria maculans and L. biglobosa are fungal pathogens able to cause allergic reactions in humans and infect plants of Brassica species. The rate of their development and subsequent spore release depend on weather conditions. The aim of this paper was to pinpoint the exact meteorological conditions triggering the release of L. maculans and L. biglobosa ascospores in central and eastern Poland. Multiple regressions indicated that the frequency and amount of rainfall over short periods were important in mediating spore release. The first ascospore event depended mainly on the number of rainy days during the first 10 days of July and the cumulative precipitation during July and September. The most important variables for maximum spore release were cumulative rainfall in the beginning of July and the end of September, as well as the number of days with precipitation events in the first 10 days of August. The results highlighted for the first time the importance of the days preceding the collection of oilseed rape plants from the field. Higher moisture content of senescing but still living stems play a crucial role in the early start of the ascospore season and the maximum release of ascospores. This was not yet considered to date. 相似文献
19.
20.
Luciano Polonelli Stefania Conti Lauresa Campani Mara Gerloni Giulia Morace Carlo Chezzi 《Antonie van Leeuwenhoek》1991,59(3):139-145
The differential toxinogenesis of 25 isolates belonging to species of the potential yeast killer genusPichia that were previously classified in the genusHansenula was comparatively demonstrated by two serologic techniques (indirect immunofluorescence and double immunodiffusion) by using a monoclonal antibody against a yeast killer toxin produced by a selected strain ofPichia anomala (UCSC 25F). The killer phenotypes of thePichia isolates were evaluated by their ability to kill each other. The results, although of insufficient taxonomic value for a reliable separation of either species or genera, attest to the genomic heterogeneity for the killer character in the genusPichia as well as the presumptive dual killer/sensitive identity for each single isolate. 相似文献