Mycobacterium alvei sp. nov.

A new species of rapidly growing, nonphotochromogenic mycobacteria, Mycobacterium alvei, is described. The inclusion of this organism in the genus Mycobacterium is based on its acid fastness, its mycolate pattern, and its G + C content. A study of six strains showed that they form a homogeneous group with an internal phenotypic similarity value of 97 +/- 2.

Lack of correlation between colony morphology and lipooligosaccharide content in the Mycobacterium tuberculosis complex.

Rough and smooth colony variants of the Mycobacterium tuberculosis complex were compared with respect to their composition in trehalose-containing glycolipid antigens in view of the results of a recent investigation suggesting that the chemical basis of rough and smooth colony morphology in mycobacteria may reside in the occurrence of lipooligosaccharides. A careful chemical characterization of the individual glycolipids of the selected strains allowed the identification of the major glycolipids. The comparative study of the glycolipid content of the smooth Canetti strain, its spontaneous rough variant, and 16 additional strains of M.

Mycobactin analysis as an aid for the identification of Mycobacterium fortuitum and Mycobacterium chelonae subspecies.

Mycobactin patterns from 65 Mycobacterium fortuitum and Mycobacterium chelonae strains have been determined by thin-layer chromatography. By use of a rich liquid medium containing an iron chelator (ethylenediamine-di-o-hydroxyphenylacetic acid [EDDA]) to ensure iron starvation, all strains were able to form mycobactins. The method developed here allows sensitive detection of mycobactin by thin-layer chromatography from as little as 5 ml of culture after a 2-week incubation.

Proposed minimal standards for the genus Mycobacterium and for description of new slowly growing Mycobacterium species.

In accordance with Recommendation 30b of the International Code of Nomenclature of Bacteria, which calls for the development of recommended minimal standards for describing new species, we propose minimal standards for describing the genus Mycobacterium and new slowly growing species of this genus. The minimal standards for assignment of a strain to the genus Mycobacterium include acid-alcohol fastness, a DNA G+C content in the range from 61 to 71 mol%, and mycolic acid detection with characterization of C22 to C26 pyrolysis esters. The recommended minimal standards for describing a new slowly growing Mycobacterium species are based on the results of phenotypic and genomic studies and include the results of the following conventional tests: growth at 25, 30, 33, 37, 42, and 45 degrees C; pigmentation; resistance to isoniazid, thiophene-2-carboxylic acid hydrazide, hydroxylamine, p-nitrobenzoic acid, sodium chloride, thiacetazone, picrate, and oleate; catalase activity; Tween hydrolysis; urease activity; niacin detection; and nitrate reductase, acid phosphatase, arylsulfatase, pyrazinamidase, and alpha-esterase activities.