Electron microscopic evidence of flagella and pili on Legionella pneumophila.

Abstract

SUMMARY Twenty-one strains of Legionella pneumophila, representing the six known serotypes of the organism, cultured on various bacteriological media and in the yolk sacs of fertile hens' eggs were examined by negative stain electron microscopy for flagella and pili. These appendages were usually observed after cultivation on media capable of inducing an early profuse growth of the organisms.

Temperature-dependent expression of flagella in Legionella

“…Freeze-etching studies did not reveal a crystalline S-layer, although such proteinaceous surface structures can be found in a variety of bacteria (Sleytr & Messner, 1988b). We were also unable to detect fimbriae which have been described by Chandler et al (1980) and Rodgers et al (1980). The failure to detect fimbriae might be due to differences in the growth conditions used, as Rodgers et al (1980) reported the presence of fimbriae after cultivation in broth or on enriched blood agar.…”

“…The chemistry of lipopolysaccharide, determining the different serogroups (Conlan & Ashworth, 1986), has been elucidated for L. pneumophila (Sonesson et al, 1989). Capsules have not been detected (Hebert et al, 1984), but some authors report the presence of fimbriae and flagella (Chandler et al, 1980;Rodgers et al, 1980). In this report we further analysed the surface of L. pneumophila for crystalline surface (S) layers (Sleytr & Messner, 1988 a ) and focussed our studies on the expression of flagella in L. pneumophila and other Legionella species.…”

Identification of Legionella Pneumophila Antigens and Antibodies by Immunoferritin Electronmicroscopy

“…Similarly, organisms have been identified in thin sections of lung tissues (Rodgers, 1979b). This report amplifies the value of IFEM in the detection of legionellae by the examination of formalin-fixed post-mortem lung tissues, suspensions of infected yolk-sac membranes, and bacterial suspensions.…”

“…In a preliminary report on a limited number of specimens, immunoferritin electronmicroscopy (IFEM) was shown to be useful for identifying L. pneumophila serogroup-1 organisms in suspensions (Rodgers and Macrae, 1979). Similarly, organisms have been identified in thin sections of lung tissues (Rodgers, 1979b).…”

“…The better resolution and higher magnification afforded by negative-stain and thin-section electronmicroscopy show the organisms to have a distinctive morphology (Rodgers, Macrae and Lewis, 1978), are found intracellularly in lung macrophages (Rodgers, 1979b;Chandler et al, 1979), and possess flagella and pili (Rodgers et al, 1980;Chandler et al, 1980). The antigens of legionellae and the antibodies they induce in human sera have been detected with varying success by several means, including micro-agglutination, enzyme-linked immunosorbent assay (Farshy, Klein and Feeley, 1978), and counter immunoelectro-phoresis (Holliday, 1980).…”