Chemotaxonomic Characters and Classification of Some Nocardioform Bacteria

Abstract

S U M M A R YSimple chemical analyses were carried out on I 98 nocardioform bacteria by means of paper-and thin-layer chromatography. The strains considered to belong to the genus Nocardia contained the lipid LCN-A, arabinose and meso-diaminopimelic acid. All the representative strains from the 'Mycobacteriurn ' rhodochrous complex possessed this lipid though in certain cases the characteristic spot had a slightly lower RF value than that of the reference lipid LCN-A from the standard strain of Nocardia asteroides. The genera Actinomadura, Mycobacterium, Oerskovia and Streptomyces did not contain lipid LCN-A and the distribution of the other two chemical characters varied. The method used to detect lipid LCN-A is simple and reliable and permits the separation of nocardias and 'M.' rhodochrous strains from allied taxa. These results correlate well with other trends in the taxonomy of nocardioform bacteria and confirm the value of chemotaxonomic characters, especially lipids, in the classification and identification of these organisms.

Mycolic acids of representative strains of Nocardia and the ‘rhodochrous’ complex

“…The discovery that the mycolic acids of a typical strain of the 'rhodochrous' complex have a lower molecular weight range than those of the major acids from Nocardiu caviue is consistent with the relatively lower TLC mobility of the mycolic acids from some [2] to be clearly distinct from strains of Norcardia and Colynebacterium. In this connection, the detailed relation of two strains of nocardioform bacteria, N. farcirzica IM 1377 [4] and N. erythropolis [ 111, having mycolic acids in the molecular weight range C32 to C48 to strains of the 'rhodochrous' complex would repay investigation.…”

“…Nocardia cake NCTC 1934 and a representative of the 'rhodochrous' complex (Nocardia calcarea NCIB 8863) were grown in modified Sauton's medium, tested for purity and harvested as described previously [2] . A lipid extract was prepared from freeze-dried cells by soaking in ethanol-diethyl ether (1: 1) overnight and removing the extracted cells by filtration; the extraction solvents were removed by evaporation under reduced pressure at low temperature (< 37°C).…”

“…Mycolic acids have been isolated and characterised from Mycobacteria, Nocardiae and Corynebacteria [ I] . Characteristic lipids detected by thin-layer chromatography (TLC) in strains of Nocardiae and organisms of the closely related 'rhodochrous' complex [2] have recently been shown to be free mycolic acids [3]. It was noted [2] that the characteristic lipids of many 'rhodochrous' strains had a significantly lower RF value on TLC than those from cultures of Nocardia sensu stricto.…”

“…Characteristic lipids detected by thin-layer chromatography (TLC) in strains of Nocardiae and organisms of the closely related 'rhodochrous' complex [2] have recently been shown to be free mycolic acids [3]. It was noted [2] that the characteristic lipids of many 'rhodochrous' strains had a significantly lower RF value on TLC than those from cultures of Nocardia sensu stricto. This report will demonstrate that the mycolic acids of a representative of the 'rhodochrous' complex are of significantly lower molecular weight than those of a typical Nocardia strain.…”

Nocardia flavorosea sp. nov.

“…Strain JCM 3332T (= NRRL B-16176T) was grown at 30 "C for 7 d in shake flasks containing modified Sauton's broth (Modarska et al, 1972). Biomass for the chemotaxonomic studies was collected by centrifugation, washed twice with distilled water and freeze-dried.…”