Invasion of HeLa cells by Mycoplasma penetrans and the induction of tyrosine phosphorylation of a 145-kDa host cell protein

Abstract

The ability of Mycoplasma penetrans to invade eukaryotic cells was studied using a HeLa cell line. The bactericidal antibiotic, gentamicin, in combination with low concentrations of Triton X-100, was utilized to kill mycoplasmas that had not entered the cells, allowing the quantitation of internalized organisms. The intracellular location of the mycoplasma was also documented by transmission electron microscopy. The actin polymerization inhibitor cytochalasin-D markedly inhibited the internalization process, whereas the tyrosine phosphorylation inhibitors, staurosporin and genistein had only a slight effect. As against the invasion of enteropathogenic Escherichia coli which depends on tyrosine phosphorylation of a 90-kDa (Hp90) HeLa cell protein, internalization of M. penetrans by HeLa cells was independent of the phosphorylation of Hp90. Nonetheless, tyrosine phosphorylation of a 145-kDa HeLa cell protein was found to be associated with the interaction of M. penetrans with HeLa cells.

Identification of two glycosylated components of Mycoplasma penetrans: a surface-exposed capsular polysaccharide and a glycolipid fraction

“…Mycoplasma penetrans was only recently isolated, initially from HIV-infected patients, and has unique morphology (Lo et al, 1991). It is cytopathic and capable of adhesion to, and invasion of, mammalian epithelial cells (Andreev et al, 1995;Giron et al, 1996;Lo et al, 1993). It is associated with HIV infection, at least among homosexual patients (Grau et al, 1995;Wang et al, 1993).…”

Molecular Biology and Pathogenicity of Mycoplasmas

“…Invasion of enteropathogenic Escherichia coli depends on tyrosine phosphorylation of a 90-kDa HeLa cell protein. This was not found to be the case for M. penetrans, although tyrosine phosphorylation of another HeLa cell protein of 140 kDa could probably be associated with the internalization of M. penetrans (11).…”

“…Other cytoskeletal components, such as talin, tropomyosin, and vinculin did not appear to accumulate at the site of mycoplasma clustering, suggesting that M. penetrans selectively uses signals to induce specific cytoskeletal rearrangements (156). Along these lines, Andreev et al (11) reported that the actin polymerization inhibitor cytochalasin D markedly inhibited the internalization of M. penetrans in HeLa cells whereas the tyrosine phosphorylase inhibitors staurosporin and genistein had only a slight effect. Invasion of enteropathogenic Escherichia coli depends on tyrosine phosphorylation of a 90-kDa HeLa cell protein.…”

Mycoplasma Removal from Cell Culture Using Antimicrobial Photodynamic Therapy

“…In mycoplasmas, Mycoplasma fermentans, which frequently contaminates cell culture, 18 and Mycoplasma penetrans are known to have invasive properties. 19,20 Recently, O'Riordan et al 21 have reported that 50% of intracellular Mycobacterium bovis were killed using aPDT, compared with extracellular bacteria, when they are cocultured with macrophages, suggesting that aPDT may be applicable to killing intracellular bacteria. However, there are still few reports on the application of aPDT for killing intracellular bacteria, and further studies are needed to develop a method that is able to completely remove the mycoplasmas that have host cell-invasive properties from the contaminated cells.…”