APPLIED MICROBIOLOGY, May 1970, P. 862-864 Copyright © 1970 American Society for Microbiology Vol. 19, No. 5 Printed in U.S.A. NOTES Black Beauty Out of Mycobacterium fortuitum Cruz RUTH E. GORDON AND C. HOR-NAY PANG Institute of Microbiology, Rutgers University, New Bruinswick, New Jersey 08903 Received for publication 19 January 1970 A black-pigmented strain developed Mycobacterium fortuitum. spontaneously from a typical strain of In 1958, our strain no. 1000 was received from C. H. Collins, Public Health Service, County Hall, London, as his strain no. 3 of Myco- bacterium species, a strain described as non- pigmented (Fig. IA) and arylsulfatase-positive. Shortly after its arrival, cultures of the strain were lyophilized. Our tests and observations (3), completed in 1959, showed strain no. 1000 to be a typical strain of M. fortuitum (Table 1). After 10 years of storage at 4 C, during a routine examination of our lyophilized cultures, strain no. 1000 was revived on a slant of yeast- dextrose-agar (9). One black-pigmented colony appeared among several isolated colonies above the confluent growth on the slant. The black colony was picked, and growth of the resulting deeply pigmented strain is shown in Fig. lB. In addition to its black growth, this strain produced some dark, soluble pigment. Cultures of the strain were strongly acid-fast, and its morphology was typical of the more rapidly growing myco- bacteria. Except for less activity on trehalose, the black-pigmented strain had the same physio- logical characteristics as its parent strain (Table 1). The pigmentation of cultures of M. fortuitum on various media, varying from straw-colored to black, has been described (1, 2, 5-8, 10). Oc- casionally, old cultures of M. Jortuitum on glycerol-agar (containing soil extract) formed a deep black soluble pigment (4); the growth, however, remained whitish, and subcultures of these pigment-forming old cultures did not blacken the medium. The black-pigmented daughter strain from our strain no. 1000 is the only M. Jortuitum to produce black growth that we have observed. As shown in Fig. 1C, sectors of the original whitish growth appeared in some cultures of the black strain, and the dark pigment is not a stable property of the strain. This investigation was supported by Public Health Service grant AI-06276 from the National Institute of Allergy and Infec- tious Diseases. LITERATURE CITED 1. Cerb6n, J., and L. F. Bojalil. 1961. Physiological relationships of rapidly growing mycobacteria. J. Gen. Microbiol. 25:7-1 5. 2. Cerb6n, J., and A. Trujillo. 1963. A comparison of methods for the classification of mycobacteria, utilization of carbon sources and deamidase tests. Amer. Rev. Resp. Dis. 88:546- 550. 3. Gordon, R. E. 1966. Some strains in search of a genus- Corynebacterium, Mycobacterium, Nocardia or what? J. Gen. Microbiol. 43:329-343. 4. Gordon, R. E., and J. M. Mihm. 1959. A comparison of four species of mycobacteria. J. Gen. Microbiol. 21:736-748. 5. Kushner, D. S., S. McMillen, and M. Senderi. 1957. Atypical acid-fast bacilli. II. Mycobacterium fortuitum: bacteriologic characteristics and pathenogenicity for laboratory animals. Amer. Rev. Tuberc. 76:108-122. 6. Moore, M., and J. B. Frerichs. 1953. An unusual acid-fast infection of the knee with subcutaneous, abscess-like lesions of the gluteal region. J. Invest. Dermatol. 20:133-169. 7. Ross, A. J. 1960. Mycobacterium salmoniphilium sp. nov. from salmonoid fishes. Amer. Rev. Resp. Dis. 81:241-250. 8. Tsukamura, M. 1965. Salicylate degradation test for differ- entiation of Mycobacterium fortuitum from other myco- bacteria. J. Gen. Microbiol. 41:309-315. 9. Waksman, S. A. 1950. The actinomycetes, p. 196. Chronica Botanica Co., Waltham, Mass. 10. Wells, A. Q., E. Agius, and N. Smith. 1955. Mycobacterium fortuitum. Amer. Rev. Tuberc. 72:53-63. 862 FIG. 1. Growth of Mycobacterium fortuitum on yeast-dextrose-agar. (A) Original straint no. 1000; (B, C) strain n1o. 1000 black. Incubation, 3 weeks. X 2. o n A p ril 5 , 2 0 2 1 a t C A R N E G IE M E L L O N U N IV L IB R h ttp ://a e m .a sm .o rg / D o w n lo a d e d fro m http://aem.asm.org/ .>. . @ _ R < . o n A p ril 5 , 2 0 2 1 a t C A R N E G IE M E L L O N U N IV L IB R h ttp ://a e m .a sm .o rg / D o w n lo a d e d fro m http://aem.asm.org/ APPL. MICROBIOL. TABLE 1. Some physiological reactionts of Myco- bacterium fortuitum Ir,rn-Y Decomposition of Casein ................ Tyrosine .............. Urea ................. Deamination of phenyl- alanine ............... Hydrolysis of Starch ................ Hippurate ......... Growth at 45 C ............... 40 C ............... 28 C................. Survival at 60 C, 4 hr. Acid from Arabinose ......... Dulcitol ............ Erythritol ........... Galactose ............ Glucose ............ Inositol .............. Lactose ............... Mannitol .......... Mannose .............. a-m-D-Glucoside .... Raffinose.............. Rhamnose. Sorbitol. Trehalose ............. Xylose .. . ...... Utilization of Benzoate ........... Citrate ............. Lactate ............. Malate .............. Mucate ........ Oxalate...... ........ Succinate ............. Growth on dyes Methyl violet ....... Pyronin ............... Color change of Mac- Conkey agar. Resistance to Penicillin, 10 units. Bacitracin, 10 units.... Production of arylsul- fatase, 3 days......... Growth in (0.2%) sali- cylate broth........... Strain Strainn0 1000 150 Strains of i9 uuu black M. fortuiititm(15) (1968) + + + + +r + + a ± + + ± + + ± + + ± + + + ± ± A- + - (0)h - (0) + (94) - (I) + (94) + (95) - (5) + (70) + (100) - (0) -(2) - (0) - (12) - (8) + (98) - (9) - (0) F (28) ± (98) - (0) - (1) - (0) - (3) + (96) - (3) - (3) ± (82) ± (98) + (97) - (0) - (0) + (98) + (99) ± (100) + (98) + (100) ± (85) + (96) ± (83)d Symbols: +, 85 to 100%' of strains positive; ±, 50 to 841'' of strains positive; F, 15 to 49% of strains positive; -, 0 to 14%,7- of strains positive. Numbers in parentheses represent per cent positive strains. c Trace. d Only 52 strains were tested. 864 NOTES o n A p ril 5 , 2 0 2 1 a t C A R N E G IE M E L L O N U N IV L IB R h ttp ://a e m .a sm .o rg / D o w n lo a d e d fro m http://aem.asm.org/