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M Goodfellow

Publications and source records attributed to M Goodfellow.

At least 145 records · Page 8Linked to original sources

Fatty acid, isoprenoid quinone and polar lipid composition in the classification of Curtobacterium and related taxa.

Strains representing the taxa Curtobacterium, Brevibacterium saperdae, B. testaceum, Corynebacterium betae, Cor. nebraskense and Cor. oortii were degraded by acid methanolysis and the non-hydroxylated fatty acid esters released were examined by thin-layer and gas-liquid chromatography. The major fatty acids in all strains were 12-methyltetradecanoic (anteiso C15) and 14-methylhexadecanoic (anteiso C17) acids which occurred together with other anteiso, iso and straight-chain acids. Polar lipids of the test strains were examined by two-dimensional thin-layer chromatography. All organisms possessed very characteristic polar lipid patterns consisting of diphosphatidylglycerol, phosphatidylglycerol and a number of uncharacterized glycolipids. The menaquinone components of the test strains facilitated their division into two groups containing, respectively, nine isoprene units (viz. Curtobacterium citreum, Curt. luteum, Corynebacterium betae, Cor. flaccumfaciens, Cor. oortii, Cor. poinsettiae and Cor. nebraskense) and eleven and twelve isoprene units (viz. Brevibacterium saperdae, B. testaceum). The results of the present study indicate that the genus Curtobacterium as presently recognized is a heterogeneous taxon containing two distinct centres of variation.

Actinomycetales↗

Numerical classification of some named strains of Nocardia asteroides and related isolates from soil.

One hundred and forty-nine strains of nocardiae, freshly isolated from soil samples obtained from a number of countries with either tropical or temperate climates, and from rubber pipe seals, were compared with appropriate marker cultures in a numerical phenetic study using 156 unit characters. Marker strains were chosen to represent the Nocardia asteroides complex, other Nocardia species and related taxa in an effort both to classify the new soil isolates and, possibly, clarify the structure of the heterogeneous N. asteroides complex. The data were examined using the simple matching (SSM) and pattern (DP) coefficients, and clustering was achieved using both single and average linkage algorithms. Cluster composition was not markedly affected by either of the coefficients or clustering methods. The estimated test error of 7.1% was rather high and could account for a few apparently anomalous results. The 16 defined clusters, containing 185 of the 197 strains studied, were divided into seven major and nine minor clusters, four of which were further subdivided into two subclusters. Marker strains allowed four clusters to be designated as N. asteroides, seven as Nocardia species and one each as Nocardia carnea, Nocardia farcinica, Nocardia autotrophica, Mycobacterium farcinogenes and Rhodococcus species. Twelve strains formed single member clusters including the type strains of Nocardia aerocolonigenes, Nocardia amarae, Nocardia fukuyae, Nocardia orientalis and Nocardia otitidis-caviarum. The majority of the soil and rubber isolates were recovered in the major clusters labelled N. asteroides, N. carnea and Nocardia species and clusters of soil isolates without marker strains seem to represent new centres of variation. The study highlights the need for additional reproducible tests to help both define and determine the status of defined clusters within the N. asteroides complex which would considerably benefit both the ecological and epidemiological study of these organisms.

Nocardia asteroides↗

Ribosomal ribonucleic acid similarities in the classification of Rhodococcus and related taxa.

Duplexes were prepared between 14C-labelled rRNA from both Rhodococcus equi C7 and Rhodococcus rhodochrous N54 and DNA from 16 actinomycetes representing the genera Rhodococcus, Mycobacterium, Nocardia, Saccharopolyspora and Streptomyces. The relationships between the organisms were determined by plotting the temperature at which 50% of the duplex was denatured (Tm(e)) against the percentage of rRNA binding (microgram 14C-labelled rRNA duplexed per 100 micrograms filter-bound DNA). All of the strains formed stable duplexes but each organism occupied a definite area on the rRNA similarity map. All of the organisms share a close phylogenetic relationship but representatives of the genera Rhodococcus, Mycobacterium, Nocardia and Streptomyces fell into four recognizable clusters on the similarity map. These data support and extend current trends in the classification of Rhodococcus and allied taxa. The guanine plus cytosine content of the DNA from the test strains was within the range 69.3 to 76.9 mol %.

Actinomycetales↗

A taxonomic study of Gardnerella vaginalis (Haemophilus vaginalis) Gardner and Dukes 1955.

Fifty-five strains received as Haemophilus vaginalis or as catalase-negative coryneform bacteria from the vagina together with 61 marker cultures were subjected to numerical phenetic analyses using 149 unit characters. The data were examined using the simple matching (SSM), Jaccard (SJ) and pattern (DP) coefficients and clustering was achieved using the average linkage algorithm. Cluster composition was not markedly affected by the coefficient used or by test error, estimated at 6 . 5%. The H. vaginalis strains formed a tight cluster which was only distantly related to representatives of the genera arthrobacter, Cellulomonas, Corynebacterium sensu stricto, Erysipelothrix, Haemophilus, Kurthia, Lactobacillus, Listeria and Propionibacterium but shared a high overall affinity to unclassified catalase-negative coryneforms which formed a discrete taxon, cluster 9. The H. vaginalis strains could be distinguished from the related strains in cluster 9 by several unrelated phenotypic characters. Using the S1 endonuclease assay, DNA-DNA hybridizations were performed with representative strains from the numerical as well as with reference strains of Bifidobacterium and Actinomyces. Haemophilus vaginalis was found to be a genotypically legitimate group and its DNA showed little homology with DNA from the marker strains tested. The DNA base composition of H. vaginalis was 42 to 44 mol % guanine plus cytosine. A new genus should be created to incorporate strains known as H. vaginalis or Corynebacterium vaginale. The name Gardnerella vaginalis proposed by Greenwood & Pickett (1979) is supported.

Base Composition↗

Distribution of beta-glucanases within the genus Bacillus.

Representative strains (368) from 36 species in the genus Bacillus were screened for the secretion of beta-glucanases. (1 leads to 6)-beta-glucanases active on pustulan were produced by a minority of the organisms studied (4%), but (1 leads to 3)-beta-glucanases which hydrolyzed laminarin and pachyman were more widespread and were secreted by 56 and 44% of the strains, respectively.

Bacillus↗

Polynucleotide sequence divergence among some coagulase-negative staphylococci.

The degree of binding was determined, at both exacting and non-exacting temperatures, between deoxyribonucleic acid (DNA) preparations from coagulase-negative staphylococci and carbon (14C) labelled DNA from nine reference strains, Staphylococcus capitis LK499, S. cohnii GH137, S. epidermidis GH37, S. haemolyticus SM131, S. hominis DM122, S. saprophyticus CCM883, S. simulans SM128, S. warneri AW25 and S. xylosus KL162. The close similarity in nucleotide sequences found between five of the six representatives received as S. capitis, S. hominis and S. warneri indicate that these organisms are separated into too many species. In contrast, little homology was found between the pairs of strains representing S. cohnii and S. haemolyticus, respectively. The divergence indices of the nine reference strains were calculated and the relationship between them expressed in a sorted similarity matrix and dendrogram based upon the average linkage algorithm. The pattern of nucleotide heterogeneity was found by plotting the relative DNA bound at the exacting temperature against the divergence indices. The coagulase-negative staphylococci exhibit extensive genetic diversity due mainly to random mutation.

DNA, Bacterial↗

Isoprenoid quinones in the classification of coryneform and related bacteria.

Menaquinones were the only isoprenoid quinones found in 85 of the 95 coryneform bacteria examined. Dihydromenaquinones having nine isoprene units were the main components isolated from Corynebacterium bovis, from other glutamic acid-producing strains, and from Arthrobacter globiformis and related species. Dihydromenaquinones with eight isoprene units were found in Brevibacterium linens, the remaining Corynebacterium species and strains probably belonging to the genus Rhodococcus. Tetrahydromenaquinones with eight isoprene units were found in Arthrobacter simplex and Arthrobacter tumescens, and with nine isoprene units in Cellulomonas and Oerskovia. Kurthia and Curtobacterium were characterized by menaquinones with seven and nine isoprene units, respectively, and Microbacterium lacticum and Corynebacterium aquaticum had comparable amounts of menaquinones with 10 and 11 isoprene units. Strains received as Brevibacterium leucinophagum, Corynebacterium autotrophicum, Corynebacterium nephridii, Mycobacterium flavum, Mycoplana rubra and Protaminobacter ruber contained uniquinones as their sole isoprenoid quinones. The isoprenoid quinone data correlate well with major trends in coryneform taxonomy and are of value in the classification of coryneform and related bacteria.

Actinomycetales↗

Numerical taxonomy of Actinomadura and related actinomycetes.

One hundred and fifty-six Actinomadura strains, marker strains of related taxa, and related isolates from bagasse and fodder were the subject of numerical phenetic analyses using 90 unit characters. The data were examined using the simple matching (SSM), Jaccard (SJ) and pattern (DP) coefficients and clustering was achieved using both single and average linkage algorithms. Cluster composition was not markedly affected either by the coefficient or clustering algorithms used or by test error, estimated at 4.5%. Actinomadura dassonvillei, Actinomadura madurae and Streptomyces somaliensis formed good taxospecies, but the separation of Actinomadura pelletieri strains into two clusters by SJ and SSM analysis requires further study. The single representatives of Actinomadura helvata, Actinomadura pusilla, Actinomadura roseoviolacea, Actinomadura spadix and Actinomadura verrucosopora seemed to form new centres of variation while Actinomadura citrea and Actinomadura malachitica showed much similarity with Actinomadura madurae. Most of the isolates form bagasse and fodder were recovered in two well-defined phena, provisionally labelled clusters 'A' and 'B' which showed little similarity to either Actinomadura or Nocardia strains. The effect of the different coefficients on the aggregation of clusters is discussed.

Nocardiaceae↗

The actinomycete-genus Rhodococcus: a home for the "rhodochrous" complex.

A numerical taxonomic classification study was carried out on 177 strains representing the "rhodochrous" complex and the genera Gordona, Mycobacterium and Nocardia. The strains were examined for 92 unit characters and the data were analysed by computer. Three clusters were defined at the 75 to 80% similarity level. The first was a heterogeneous cluster corresponding to the "rhodochrous" taxon whereas the other two contained Mycobacterium and Nocardia strains respectively. The good correlation between the numerical analysis and chemo-taxonomic, serological and genetical data collected from previous studies provides sufficient evidence for raising the "rhodochrous" taxon to generic status. We consider the generic name Rhodococcus Aopf to have priority over Proactinomyces (Jensen) Bradley & Bond, Jensenia Bisset & Moore and Gordona Tsukamura. In addition to the type species, Rhodococcus rhodochrous, nine species are recognized: R. bronchialis, R. coprophilus, R. corallinus, R. erythropolis, R. equi, R. rhodnii, R. rubrus, R. rubropertinctus and R. terrae.

Genetics, Microbial↗

Distribution of menaquinones in actinomycetes and corynebacteria.

Menaquinones were the only isoprenoid quinones found in 48 corynebacteria and actinomycete strains examined. Dihydromenaquinones having nine isoprene units were the main components isolated from Gordona, Mycobacterium, Corynebacterium bovis, Corynebacterium glutamicum and a strain labelled Nocardia farcinica, but dihydromenaquinones having eight isoprene units were characteristic of other Corynebacterium species and representatives of the 'rhodochrous' complex. Tetrahydromenaquinones having six and eight isoprene units were found in Nocardia strains and in a single strain of Micropolyspora brevicatena, which also contained mycolic acids similar in chain length to those of Nocardia. Menaquinones having nine isoprene units with from one to five double bonds hydrogenated were the main components in Actinomadura madurae, Actinomadura pelletieri, Micropolyspora faeni, Oerskovia turbata and Streptomyces strains. Actinomadura dassonvillei strains had a characteristic pattern of di-, tetra- and hexahydromenaquinones with 10 isoprene units which was slightly different from the pattern in mixtures of similar quinones from Actinomyces israelii and Actinomyces viscosus.

Corynebacterium↗

Fatty and mycolic acid composition of Bacterionema matruchotii and related organisms.

Whole-organism methoanolysates of bacterionemae contained mycolic acids in addition to other long-chain fatty acids. These mycolic acids were similar in general structure and overall size to those found in strains of Corynebacterium diphtheriae and Corynebacterium xerosis. The long-chain fatty acids of bacterionemae, mainly straight-chain saturated and unsaturated acids, were similar to those of certain coryneform bacteria including C. diphtheriae. On the basis of these lipid data, and results of earlier studies, we recommend that the genus Bacterionema be transferred from the family Actinomycetaceae to the Coryneform Group of Bacteria.

Actinomycetaceae↗

Antagonistic interactions of phylloplane bacteria with Drechslera dictyoides (Drechslera) Shoemaker.

Strains of Listeria denitrificans (E2), Pseudomonas fluorescens (C37 and C92), and Xanthomonas campestris (D119), isolated from the phylloplane of Lolium perenne (S24), were antagonistic to Drechslera dictyoides (Drechslera) Shoemaker. From in vitro and in vivo experiments it was deduced that their mode of activity included an initial inhibition of spore germination, a retardation in the rate of germ-tube elongation, and ultimately lysis of the hyphae. The effects were expressed on the plant in terms of reduced levels of disease symptoms and sporulation.

Culture Media↗