Disease relevance of Naegleria

• Mouse peritoneal macrophages activated by different immunomodulators (Mycobacterium bovis bacillus Calmette-Guérin or Propionibacterium acnes) destroy Naegleria fowleri amoebae by a contact-dependent process and by soluble cytolytic molecules secreted by macrophages in response to lipopolysaccharide [1].
• Peritoneal macrophages activated in vivo by bacillus Calmette-Guérin or Propionibacterium acnes demonstrated significant cytolysis of Naegleria fowleri amoebae [2].
• High-resolution polyacrylamide gradient gel electrophoresis (PGGE) was used to separate isoenzymes of 12 Naegleria strains: one N. australiensis, two N. lovaniensis, one N. jadini, two N. gruberi isolated from environmental samples, and six N. fowleri strains isolated from patients with primary amoebic meningoencephalitis [3].

High impact information on Naegleria

• Naegleria fowleri: trimethoprim sensitivity [4].
• Growth inhibition of Naegleria fowleri by tetracycline, rifamycin, and miconazole [5].
• Naegleria heat shock proteins are, however, strikingly similar in size to a group of heat-induced proteins found in chick embryo fibroblast, mouse L, and BHK cells [6].
• The 44 kDa component was identified as the Naegleria homologue of fibrillarin [7].
• Our data indicate that in one lineage of Naegleria the group I intron lost part of its DNA that is not contributing to the secondary structure but that carries the open reading frame [8].

Biological context of Naegleria

• First, a mutant yeast strain was selected with a mutation in all the rRNA genes, rendering the rDNA resistant to cleavage by the Naegleria endonuclease [9].
• These findings suggest a role for TNF-mediated destruction of Naegleria trophozoites by neutrophils in host defense, and that ingestion of host neutrophils by Naegleria trophozoites may represent a virulence factor [10].
• I-NjaI, a nuclear intron-encoded homing endonuclease from Naegleria, generates a pentanucleotide 3' cleavage-overhang within a 19 base-pair partially symmetric DNA recognition site [11].
• The ability of Naegleria to activate the alternative complement pathway was demonstrated with the use of C2-deficient serum [12].
• We previously cloned an antigenic gene (named nfa1) from a cDNA library of Naegleria fowleri by immunoscreening [13].

Anatomical context of Naegleria

• The arginine-dependent cytolytic mechanism plays a role in destruction of Naegleria fowleri amoebae by activated macrophages [1].
• Role of myeloperoxidase in the killing of Naegleria fowleri by lymphokine-altered human neutrophils [14].
• Antibodies to bacterially expressed Naegleria centrin, which also recognize yeast Cdc31p, were employed to localize centrin immunoreactivity in selected organisms possessing specialized microtubule-organizing centers (MTOCs) or accessory structures [15].

Associations of Naegleria with chemical compounds

• Exposure of axenic cultures of the amoeboflagellate Naegleria gruberi EGs to the thymidine analogue 5-bromo-2'-deoxyuridine (BrdU) resulted in the induction of virus-like particles (VLP) and various structures associated with their development and presumed transmission [16].
• 5-Bromodeoxyuridine-induced formation of virus-like particles in Naegleria gruberi EGs [16].
• A beta-tubulin gene of Naegleria encodes a carboxy-terminal tyrosine. Aromatic amino acids are conserved at carboxy termini [17].
• In vitro effects of amphotericin B on growth and ultrastructure of the amoeboflagellates Naegleria gruberi and Naegleria fowleri [18].
• Cloning, sequencing and expression of the pyrophosphate-dependent phosphofructo-1-kinase from Naegleria fowleri [19].

Gene context of Naegleria

• Identification of a Naegleria fowleri membrane protein reactive with anti-human CD59 antibody [20].
• Studies were conducted on 27 Old World monkeys to determine their susceptibility to pathogenic strains (HB-1 and C-66) of Naegleria fowleri by intranasal, intravenous, or intrathecal inoculation of trophozoites [21].
• A group I intron in the small subunit ribosomal RNA gene from Naegleria andersoni ssp. andersoni strain PPMFB-6 [22].
• srRNA evolution and phylogenetic relationships of the genus Naegleria (Protista: Rhizopoda) [23].
• The encoded beta-tubulin is strongly conserved, with features that closely resemble the beta-tubulins of diverse organisms, especially organisms that, like Naegleria, use tubulin to assemble flagellar axonemes [17].

Analytical, diagnostic and therapeutic context of Naegleria

• A group I intron in the SSUrDNA of some Naegleria spp. demonstrated by polymerase chain reaction amplification [24].
• Acid extracts labelled with the fluorescent reagent monobromobimane and separated by HPLC have enabled the detection of low-molecular-mass thiol compounds in Naegleria fowleri for the first time [25].
• Indirect immunofluorescence staining was negative for Naegleria fowleri and Willaertia sp. The isolate was sensitive to azithromycin, but not to amphotericin B, pentamidine isethionate, fluconazole, 5-fluorocytosine, and sulfadiazine [26].

References