摘要:

SUMMARYThe new speciesCephaloascus albiduswas isolated from cranberry pumace in Nova Scotia, Canada. It differs from the only other known species ofCephaloascus, C. fragrans, in assimilating a greater number of compounds and in being nonpigmented and heterothallic.

ISSN:0027-5514    

DOI:10.1080/00275514.1977.12020093

出版商:Taylor&Francis    

年代:1977

数据来源: Taylor

摘要:

SUMMARYParasexual crosses involving a mutant ofAspergillus flavushaving a high and relatively stable level of aflatoxin B2relative to aflatoxin B1have revealed a genetic locus for control of aflatoxin synthesis. Five different diploids, each heterozygous for high aflatoxin B2levels, accumulated low amounts of B2but high amounts of B1. Although the haploid segregants from these diploids included a variety of aflatoxin phenotypes, one-half produced more B1than B1and one-half produced less B2than B1. Five different diploids, each homozygous for high aflatoxin B2levels accumulated high amounts of B2as did all haploid segregants from these diploids. A single genetic locus is thought to control the higher aflatoxin B2than B1accumulation in this mutant.

ISSN:0027-5514    

DOI:10.1080/00275514.1977.12020094

出版商:Taylor&Francis    

年代:1977

数据来源: Taylor

摘要:

SUMMARYThermophilic and thermotolerant fungi were quantitatively isolated from soil samples collected near Bloomington, Indiana, on eight separate dates throughout the summer of 1975. Samples were collected from each of four different field sites which differed in amount of sun heating and in amendment with organic matter. Eighteen species of thermophilic and thermotolerant fungi were isolated. Fungal growth is described on the basis of observation of in situ growth and results of plate counts. Growth rates of thermophilic and mesophilic soil fungi were measured in vitro in soil, alone and in pairs, at 20 and 37 C, and at fluctuating temperatures. The role of sun-heating of temperate soil in allowing growth of thermophilic and thermotolerant fungi, and in inhibiting growth of mesophilic fungi, is evaluated in view of the in vitro and in situ data presented. Evidence is presented in support of the conclusions that the high minimum temperature for growth of thermophilic fungi is not a laboratory artifact, and that tolerance to microbial antagonism is not necessarily low in thermophilic fungi. No evidence was found that production of antagonistic chemical compounds by thermophilic fungi was enhanced by exposure of the species tested to temperatures lower than those required for growth.

ISSN:0027-5514    

DOI:10.1080/00275514.1977.12020095

出版商:Taylor&Francis    

年代:1977

数据来源: Taylor

摘要:

SUMMARYMitochondrial configurations of various members of the Mycetozoa were examined. It was found that all members of the Eumycetozoa (amoebae with filose pseudopodia) had tubular mitochondrial cristae. Members of the Acrasea (amoebae with lobose pseudopodia) which show differentiation into stalk and sorus were found to have plate-like mitochondrial cristae. Those acrasids with the columnar type of fruiting body and with no stalk-sorus differentiation were found to have tubular mitochondrial cristae. The mitochondrial configurations found in Oomycetes, Hyphochytridiomycetes, and other fungi are briefly noted in reference to their phylogenetic significance in conjunction with biochemical parameters. Unusual helical structures found in the mitochondria of certain isolates of the Acrasea are discussed.

ISSN:0027-5514    

DOI:10.1080/00275514.1977.12020096

出版商:Taylor&Francis    

年代:1977

数据来源: Taylor

摘要:

SUMMARYCellulolytic enzymes are produced byPoronia oedipusgrown on soluble and insoluble forms of cellulose. Cellulase production is negligible when the organism is grown in the presence of glucose. Optimal cellulolytic activity occurs at 50–55 C. Hydrolysis of filter paper is greatest atpH 4.2; but with carboxymethylcellulose as a substrate, optimal cellulase activity occurs atpH 4.4 to 5.0. Total accumulation of reducing sugar in the cellulase assay with filter paper as a substrate does not rise above 1% of the substrate concentration; with CMC as a substrate, approximately 5% conversion is reported.

ISSN:0027-5514    

DOI:10.1080/00275514.1977.12020097

出版商:Taylor&Francis    

年代:1977

数据来源: Taylor

摘要:

SUMMARYFour natural products are reported as new to the two European species of the lichen genusPseudevernia. Pseudevernia furfuraceaproduces physodic acid, oxyphysodic acid, alectoronic acid, and, in some specimens, 2′-0-methylphysodic acid. Most specimens ofP. olivetorinaproduce olivetoric and 4-O-demethylmicraphyllinic acids, but a few also contain the secondary products ofP. furfuraceawith the exception of oxyphysodic acid. A simple biochemical scheme is proposed to explain the joint occurrences of these orcinol-type depsides and depsidones. In southwestern Sweden site-to-site and within-site comparisons of the proportions of the chemotypes on the same and on different substrates showed great variations, some significant differences, but no consistent correlations. If the chemotypes are indeed biologically distinct, their complex ecologies are controlled by factors exceeding those of substrate alone.

ISSN:0027-5514    

DOI:10.1080/00275514.1977.12020098

出版商:Taylor&Francis    

年代:1977

数据来源: Taylor

ISSN:0027-5514    

DOI:10.1080/00275514.1977.12020099

出版商:Taylor&Francis    

年代:1977

数据来源: Taylor

ISSN:0027-5514    

DOI:10.1080/00275514.1977.12020100

出版商:Taylor&Francis    

年代:1977

数据来源: Taylor

ISSN:0027-5514    

DOI:10.1080/00275514.1977.12020101

出版商:Taylor&Francis    

年代:1977

数据来源: Taylor

ISSN:0027-5514    

DOI:10.1080/00275514.1977.12020102

出版商:Taylor&Francis    

年代:1977

数据来源: Taylor