Characterization of Human Cutaneous Lipophilic Diphtheroids

Abstract

SUMMARYSixty lipophilic diphtheroids (LD) isolated from human skin were characterized by a variety of morphological, biochemical, physiological and nutritional tests. The LD strains were tentatively placed into six fermentative groups and one non-fermentative group. Most LD strains required amino nitrogen, others required vitamins plus amino acids for growth. Nine LD isolates initiated growth with ammonia as a sole nitrogen source. Urea and nitrate were not utilized. A total of 149 cutaneous bacteria were compared for esterase and lipase action. Esterase activity was common but few LD strains appear capable of obtaining their required lipids by their own lipase action. The grouping scheme derived from studies with the 60 LD strains was tested as a screening procedure to recognize and categorize other LD strains. A second series of 115 cultures from seven cutaneous sites were isolated. Six of the original seven groups were identified and one additional subgroup was formed. The screening method was partially effective as a means of studying the location and types of LD strains on skin. There were 31 strains which by determinative features could be grouped as Corynebacterium xerosis-like species. Human skin appears to have an unrecognized diversity of lipophilic corynebacteria yet to be classified into species.

A Medium for the Study of the Ecology of Human Cutaneous Diphtheroids

“…Despite much research dealing with the sterilizing properties of skin and its vulnerability to infection, surprisingly little attention has been given to studying the ecology of the resident cutaneous bacteria (Marples, 1965). There appear to be many more lipophilic corynebacteria on human skin than was once thought (Smith, 1969). Information on the distribution and types of these bacilli relative to cocci is lacking as is knowledge of ecological factors that may regulate these two major groups of skin bacteria.…”

“…The sources of the reference strains used in this study were previously reported (Smith, 1969). This group included the following: American Type Culture Collection (ATCChListeria monocytogenes ATCC 153 I 3, Kurthia zopJii Md., U.S.A. : C. granulosum 3024B, C. diphtheroides 2764, C. liquefaciens 3 0 4 4~, C. pyogenes 6 3 7~ and C. lyrnphophilium PREVOT.…”

Genomic Diversity and Phylogenetic Relationships among Lipid-Requiring Diphtheroids from Humans and Characterization of Corynebacterium macginleyi sp. nov.

“…Attempts to classify these organisms on the basis of biochemical characteristics have been undertaken. Smith (26) separated lipophilic diphtheroids isolated from the skin into seven taxonomic groups, while Furness et al reported (9) ten phenotypic groups for such coryneform bacteria isolated from nonspecific urethritis corresponding to five pathogenic types ("Corynebacterium genitalium") and five saprophytic types ("Corynebacterium pseudogenitalium") of the urogenital tract (8). Analysis of their cell walls revealed the presence of arabinose, galactose, diaminopimelic acid, and corynomycolic acids (7), which are characteristic of the genus Corynebacten'um.…”

A Taxonomic Scheme for Aerobic Diphtheroids from Human Skin

“…C. xerosis (NCTC no. 7243) was not lipophilic and did not reduce nitrate, although Smith (1969a) found that the three reference strains of c. xerosis (ATCC strains) he studied all reduced nitrate; C. striatum (NCTC no. 764) did reduce nitrate and Smith could differentiate between these two species only by sugar fermentation.…”

“…10288). Breed et al (1957) state that C. bovis does not decompose carbohydrates though Smith (1969a) found that three reference strains produced acid from glucose, fructose, and galactose and one did so from maltose. C. minutissimum and C. bovis could be differentiated by other tests, for example sucrose fermentation and urease produc- Bold numbers indicate areas where group is significantly more common than at other sites.…”