α-Enolase Resides on the Cell Surface of Mycoplasma fermentans and Binds Plasminogen

Abstract

. In this study, the M. fermentans Plg binding protein was isolated by affinity chromatography of Triton X-100-solubilized M. fermentans membranes by utilizing a column of a Plg-biotin complex attached to avidin that was eluted with -aminocaproic acid. The eluted ϳ50-kDa protein was identified by mass spectrometric techniques as ␣-enolase. The possibility that ␣-enolase, a key cytoplasmatic glycolytic enzyme, resides also on the cell surface of M. fermentans was supported by an immunoblot analysis using polyclonal anti-␣-enolase antiserum, which showed that ␣-enolase was present in a purified M. fermentans membrane preparation, as well as by immunochemical criteria and by immunoelectron microscopy analysis. Our observation that Plg blocked the binding of anti-␣-enolase antibodies to a 50-kDa polypeptide band resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of M. fermentans membrane or soluble preparations further supports our notion that mycoplasmal surface ␣-enolase is a major Plg binding protein of M. fermentans.

Characterization of pyruvate dehydrogenase subunit B and enolase as plasminogen-binding proteins in Mycoplasma pneumoniae

“…The occurrence of more than a single microbial molecule interacting with a given ECM component has been reported for different species such as Streptococcus pneumoniae (Bergmann et al, 2001(Bergmann et al, , 2004 and Candida albicans (Crowe et al, 2003). The identification of M. pneumoniae enolase as a binding partner of plasminogen confirmed the theoretical prediction based on homology modelling (Chumchua et al, 2008) and was in accordance with experimental results from the mycoplasma species Mycoplasma fermentans (Yavlovich et al, 2007), M. gallisepticum (Chen et al, 2011) and Mycoplasma suis (Schreiner et al, 2012). Besides GAPDH, enolase is one of most frequent members of the class of surface-localized glycolytic enzymes, as described in phylogenetically different species such as Aeromonas hydrophila (Sha et al, 2009), Bacillus anthracis (Agarwal et al, 2008), Borrelia burgdorferi (Nogueira et al, 2012), Bifidobacterium sp.…”

“…In most cases, enolases interact with plasminogen but binding to fibronectin and laminin has also been reported (Carneiro et al, 2004;Castaldo et al, 2009;Donofrio et al, 2009). The M. pneumoniae enolase shows typical putative plasminogen-binding sites, such as lysine in the C terminus, 448 FKNIK 452 , and a lysine-rich internal motif, 268 KRYVFKKGIKAKILDEK 284 (Bergmann et al, 2003;Derbise et al, 2004;Yavlovich et al, 2007). A surprising fact was the absence of this enzyme on the surface of mycoplasma cells.…”

Network of Surface-Displayed Glycolytic Enzymes in Mycoplasma pneumoniae and Their Interactions with Human Plasminogen

“…Surface-displayed glycolytic enzymes have also been demonstrated in mycoplasmas such as the important veterinary species Mycoplasma bovis (17), Mycoplasma gallisepticum (18), Mycoplasma suis (19,20), and Mycoplasma synoviae (21), as well in the human pathogens Mycoplasma fermentans (22) and Mycoplasma genitalium (23). As described for other bacteria species, enolase (Eno) and glutaraldehyde-6-phosphate dehydrogenase (GapA) were confirmed as the main surface-located glycolytic enzymes.…”

Role of Mycoplasma pneumoniae glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in mediating interactions with the human extracellular matrix

“…Since the function of different glycolytic enzymes as binding partners of human ECM proteins has so far been confirmed for at least three species (M. pneumoniae, M. genitalium and M. fermentans; Alvarez et al, 2003;Yavlovich et al, 2007), the mechanism can be suggested for further members of the class Mollicutes. On the other hand, the occurrence of surface-associated glycolytic enzymes that play a role in the pathogenesis of other, phylogenetically unrelated micro-organisms, including Gram-positive and Gram-negative bacteria and fungal or parasite species that infect different sites of the human body, indicates a common adaptation that has developed in different host-pathogen interactions.…”

“…In the uropathogenic species Mycoplasma genitalium, which shares high homology with M. pneumoniae (Herrmann & Reiner, 1998), GAPDH was found to be surface-exposed and mediated binding to human mucin (Alvarez et al, 2003). The a-enolase of Mycoplasma fermentans, which also occurs in the human urogenital tract, is involved in the adherence of the bacteria to HeLa cells and acts as binding protein to human plasminogen (Yavlovich et al, 2007). The surfaceassociated protein MSG1 of the haemotrophic mycoplasma species Mycoplasma suis has been identified as GAPDH and contributes to the adhesion of the micro-organisms to erythrocytes (Hoelzle et al, 2007).…”