Sialidase Activity in Mycoplasma Synoviae

Abstract

SUMMARYEleven strains of the avian pathogen Mycoplasma synoviae were evaluated for the presence of sialidase activity by using the fluorogenic substrate 2′-(4-methylumbelliferyl)-α-D-Nacetylneuraminic acid and the sialidase inhibitor 2-deoxy-2,3-didehydro-N-acetylneuraminic acid. The kinetics of in vitro growth in modified Frey's medium were also assessed for each strain. Five strains had been isolated from clinically symptomatic chickens, and strains WVU1853 T and K3344 have been demonstrated to be capable of reproducing disease in specific pathogen-free chickens. All strains exhibited sialidase activity, although the amount varied 65 fold (P < 0.0001) from 1.3 x 10 −7 to 2.0 x 10 −9 activity units/colony-forming unit among strains. Strains originally isolated from clinically symptomatic birds had more (P < 0.05) sialidase activity than strains from asymptomatic birds. Strain WVU1853 T exhibited the most sialidase activity (P < 0.0001) and grew to the highest culture density (P < 0.0001) among strains, but across strains the rank correlation of growth rate with sialidase activity was not significant. Negligible activity was detected in conditioned culture supernatant fluid. This is the first report of sialidase activity in pathogenic strains of M. synoviae, which suggests a potential enzymatic basis for virulence of the organism.

Phage WO of Wolbachia: lambda of the endosymbiont world

“…In D. nodosus, VrlC contains a conserved motif typically associated with sialidases [40]. A sialidase, which cleaves glycoconjugates on cell surfaces, might be involved in pathogenesis or Wolbachia ’s ability to scavenge nutrients from the host cell as seen in a diverse range of bacteria such as Pasteurellaceae [41] and some Mycoplasma [42,43]. Notably, a weak correlation between sequence variability of VrlC and CI was observed in Culex pipiens mosquitoes [44].…”

Secreted sialidase activity of canine mycoplasmas

“…The four-fold variation among M. canis strains in specific sialidase activity of washed cells was statistically significant but much less than the 65-fold variation between high- and low-virulence strains of M. synoviae (May et al, 2007). The absence of activity in M. canis isolate LV underscores the necessity to assess multiple strains of each species to characterize the phylogenetic distribution of sialidases.…”

“…Five isolates collected from Shetland sheepdogs with various reproductive disorders, and four isolates from dogs with unknown clinical history, which were obtained during a prior survey (M.B. Brown, unpublished), were identified as M. canis by PCR-RFLP screening (Spergser and Rosengarten, 2007) confirmed by direct 16S rRNA gene sequencing (May et al, 2007). …”

“…Sialidase activity of washed cells was quantitated using the fluorogenic substrate 2′-(4-methylumbelliferyl)-α-D- N -acetylneuraminic acid (MUAN; Sigma-Aldrich, St. Louis MO) and the sialidase inhibitor 2-deoxy-2,3-didehydro- N -acetylneuraminic acid (DANA; Sigma-Aldrich) as previously described (May et al, 2007). The positive control was M. alligatoris , which expresses cell-associated but not secreted sialidase.…”

Characterization of pyruvate dehydrogenase complex E1 alpha and beta subunits ofMycoplasma synoviae

“…In chickens, local infection of MS frequently causes subclinical disease of 37 the upper respiratory tract (Buim et al, 2009; Khiari et al, 2010; Landman, 2014; Wetzel et al, 38 2010), while systemic infection of MS causes synovitis (Wetzel et al, 2010). Furthermore, 39 coinfection of MS with other respiratory pathogens, such as Newcastle disease virus, infectious 40 bursal disease virus, infectious bronchitis virus, Escherichia coli, and Mycoplasma meleagridis, 41can induce airsaculitis, thereby further increasing economic losses (Giambrone et al, 1977; 42 Kleven, 1998;Limpavithayakul et al, 2016;May et al, 2007;Rhoades, 1977; Springer et al, 43 1974;Vardaman et al, 1975). In addition to respiratory tract tropism strains and arthropathic 44 strains, oviduct tropism strains can induce eggshell apex abnormalities without any physical 45 abnormalities (Limpavithayakul et al, 2016).…”