Microscopy and genomic analysis of Mycoplasma parvum strain Indiana

Abstract

Mycoplasma parvum [Eperythrozoon parvum] is the second hemotrophic mycoplasma (hemoplasma) described in pigs. Unlike M. suis, its closest phylogenetic relative, M. parvum, is considered a non-pathogenic bacterium in this host species. Natural infection of a domestic, 6-month-old splenectomized pig with M. parvum strain Indiana is described herein. Light and scanning electron microscopy of the bacteria were performed in addition to whole genome sequencing, analysis, and comparison to the genome of M. suis strain Illinois. Neither clinical signs nor anemia were observed during the infection. Microscopy analyses revealed coccoid to rod- shaped organisms varying from 0.2 to 0.5 μm; they were observed individually or in short chains by both light and electron microscopy, however less than 30% of the red blood cells were infected at peak bacteremia. The single circular chromosome of M. parvum was only 564 395 bp, smaller than M. genitalium, previously considered the tiniest member of the Mollicutes. Its general genomic features were similar to others in this class and species circumscription was verified by phylogenomic analysis. A gene-by-gene comparison between M. suis and M. parvum revealed all protein coding sequences (CDS) with assigned functions were shared, including metabolic functions, transporters and putative virulence factors. However, the number of CDS in paralogous gene families was remarkably different with about half as many paralogs in M. parvum. The differences in paralogous genes may be implicated in the different pathogenic potential of these two species, however variable gene expression may also play a role. Both are areas of ongoing investigation.Electronic supplementary materialThe online version of this article (doi:10.1186/s13567-014-0086-7) contains supplementary material, which is available to authorized users.

Porcine hemothropic mycoplasmas infection associated with productive impact in intensive pig production

“…However, we should consider that nearly 90% of the positive animals showed SQ values lower than 10 4 copies/μL, indicating that these pigs were chronically infected and did not show severe signs of anemia [ 18 ]. Besides, it is likely possible that M. parvum is the primary pathogen associated with PH in Brazil, and this PH does not cause any clinical signs, even at the peak of the bacteremia, and yet, seems to persist at low levels in the blood [ 8 ]. On the other hand, when comparing ADWG with SQ mean on d105, a significant correlation was observed.…”

“…The concomitant presence of both PH has been previously reported in sows from southern Brazil [ 30 ]. When comparing M. suis strain Illinois to M. parvum strain Indiana, bacteremia levels, at the peak, were one log lower for M. parvum than M. suis [ 8 ] . Additionally, these two pathogens are genetically related, and the genome of M. parvum has orthologous for all the protein-coding sequences (CDS) with metabolic functions identified in the genome of M. suis [ 8 ].…”

“…When comparing M. suis strain Illinois to M. parvum strain Indiana, bacteremia levels, at the peak, were one log lower for M. parvum than M. suis [ 8 ] . Additionally, these two pathogens are genetically related, and the genome of M. parvum has orthologous for all the protein-coding sequences (CDS) with metabolic functions identified in the genome of M. suis [ 8 ]. Still, a set of unique paralogous CDS of M. suis have a higher percentage of signal peptides detected than M. parvum CDS, which could play an important role in the pathogenicity of the first [ 8 , 12 ].…”

“…Also, swine hemoplasmosis has been pointed out as a possible cause of economic losses worldwide [ 1 , 6 , 7 ]. On the other hand, M. parvum infection has been associated with the absence of clinical signs, even at the peak of bacteremia [ 8 ]. Recently, M. haemosuis was detected in fattening pigs with skin lesions, fever, and anemia [ 9 ].…”

Haemoplasmas in wild rodents: Routes of transmission and infection dynamics

“…M. haemominutum," "Ca. M. turicensis," M. haemofelis, M. haematoparvum, M. haemocanis and M. wenyonii) infecting pet and domestic animals (do Nascimento et al, 2014;Hoelzle, 2008;Sasaoka et al, 2015;Tasker et al, 2009bTasker et al, , 2010Wengi et al, 2008;Willi et al, 2007b). Thus, the transmission and persistence mechanisms of naturally occurring haemoplasmas in wild animals not subjected to antibiotics or vaccinations that do not cause disease in their mammalian host remain to be explored.…”