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M Goodfellow

Publications and source records attributed to M Goodfellow.

At least 163 records · Page 9Linked to original sources

Free mycolic acids as criteria in the classification of Gordona and the 'rhodochrous' complex.

The methyl esters of free mycolic acids from representative strains of Gordona bronchialis, G. rubra, G. terrae and Nocardia kirovani each gave, on mass spectroscopy, homologous series of anhydromycolic esters containing from one to four double bonds with the main components of the parent mycolic acids centered on 56, 58, 62 or 64 carbon atoms (total range from C52 to C66). The mycolic acids from the Gordona strains, with chain lengths centered around C60, form a group intermediate in size between nocardomycolic acids (centered around C50) and mycolie different from those of the 'rhodochrous' complex which have anhydromycolates ranging from C34 to C50. Gordonae are thus more closely related in their mycolic acid composition to Nocardia than to Mycobacterium but can be distinguished from each of these genera.

Esters↗

Free mycolic acids as criteria in the classification of Nocardia and the 'rhodochrous' complex.

The methyl esters of free mycolic acids from representative strains of Nocardia asteroides, N. brasiliensis, N. caviae and the 'rhodochrous' complex were subjected to detailed mass spectral analysis. The anhydromycolic esters of the Nocardia strains consisted of homologous series containing from zero to three double bonds, with the main components of the parent mycolic acids centred on C52 to C54 (range C46 to C58). The anhydromycolates from one rhodochrous strain, Nocardia opaca, had a molecular weight range similar to the nocardiae (C46 to C57) but the remaining rhodochrous strains gave an homologous series of anhydromycolates containing from zero to two double bonds, with the main components of the parent mycolic acids centred on C38, C42, C44 or C46 (total range from C34 to C50). The mycolic acids from the rhodochrous strains with chain lengths centred around C40 form a group intermediate in size between corynomycolic acids (centred around C32) and nocardomycolic acids (centred around C50). These data weaken the case for retaining the 'rhodochrous' complex in the genus Mycobacterium, and also show that many rhodochrous strains can be distinguished from true nocardiae and corynebacteria. These results confirm the value of lipid characters in the classification of these organisms.

Esters↗

Deoxyribonucleic acid reassociation in the classification of the 'rhodochrous' complex and allied taxa.

The degree of binding was determined between DNA preparations from gordonae and rhodochrous strains and uracil-labelled DNA from five reference strains, Nocardia asteroides NK20, N. pellegrino PII, Gordona bronchialis TI, G. terrae T5 and rhodochrous strain R90. Most of the rhodochrous and pellegrino strains fell into one of two genetically homogeneous taxa. The nucleotide sequence homology data also suggested that G. bronchialis, G. rubra, and more equivocally G. terrae, formed distinct species. However, the values for DNA relatedness between these species, and between then and the rhodochrous homology groups, were comparatively low. Only a small degree of nucleotide sequence homology was found between the N. asteroides reference system and the rest of the taxa studied. The nucleotide composition of the DNA preparations from 29 of the 30 test strains fell between 63 and 69 mol% guanine plus cytosine.

Base Sequence↗

Thin-layer chromatographic analysis of mycolic acid and other long-chain components in whole-organism methanolysates of coryneform and related taxa.

Acid methanolysates of strains representing 58 coryneform taxa were examined for mycolic acids and other long-chain constituents by thin-layer chromatography. Mycolic esters were detected in the methanolysates of true corynebacteria but not in those from plant pathogenic bacteria, Corynebacterium haemolyticum, Corynebacterium pyogenes or from representatives of the genera Arthrobacter, Cellulomonas, Curtobacterium, Kurthia or Oerskovia. Thin-layer chromatography of whole-organism methanolysates provides a simple method for distinguishing true corynebacteria from coryneforms which do not contain mycolic acids, and from nocardiae and mycobacteria which produce mycolic acids of different mobility. At present the mycolic esters of true corynebacteria cannot be clearly separated from those of some rhodochrous strains.

Actinomycetales↗

Numerical taxonomy of some yellow-pigmented bacteria isolated from plants.

Phenetic data on over 60 heterotrophic, Gram-negative, yellow chromogenic bacteria from plant material were collected and analysed using numerical taxonomic methods. Marker strains representing 42 taxa were included in the analyses. At similarity levels of 80% or above, eight distinct clusters were obtained, the first four of which included yellow chromogens. Custer I contained isolates from green healthy leaves of Agrostis tenuis, Festuca rubra, Holcus lanata, Lolium perenne and Poa pratensis, and clusters 2 and 3 consisted of isolates from Holcus lanata seeds and leaves of P. pratensis respectively. Cluster 4 contained seven subgroups and was equated with the family Enterobacteriaceae. Erwinia herbicola strains from a variety of sources formed a homogeneous subgroup, readily distinguishable from authentic strains of E. amylovora, E. carotovora, other representative erwiniae, and from all other enterobacteria studied. These data emphasize the heterogeneous nature of yellow-pigmented bacteria from plants, and support the inclusion of E. herbicola and other Erwinia species in the Enterobacteriaceae.

Bacteria↗

A novel actinomycete from sugar-cane bagasse: Saccharopolyspora hirsuta gen. et. sp. nov.

A new species of nocardioform actinomycete isolated from spontaneously heated sugar-cane bagasse is described as Saccharopolyspora hirsuta gen. et sp. nov. It has affinities with species of both Nocardia and Actinomadura but can be distinguished from both genera by its morphology, sporulation, wall and lipid analyses, antibiotic resistance, degradation and carbon utilzation tests.

Actinomycetaceae↗