Mycoplasma conjunctivae
(Barile et al., 1972)
Etymology
Gr. n. mukes – fungus, Gr. neut. n. plasma – anything formed, N.L. neut. n. Mycoplasma – fungus form; N.L. n. conjunctiva – membrane joining the eyeball to the lid, N.L. gen. n. conjunctivae – of conjunctiva
Taxonomy
Mycoplasmatales – Mycoplasmataceae – Mycoplasma – Mycoplasma conjunctivae (Hyopneumoniae cluster), closely related to Mycoplasma bovoculi (16S rRNA gene sequence similarity 95.22%) (Fig. 1)
Type strain
HRC 581T (sheep, Australia, 1968), (Fig. 2, 16S rRNA gene sequence)
Genomes
one completed (HRC 581T – Australia); one draft genome (again type strain, contaminated!) (NCBI Genome deposit per 11/05/2024)
Cell morphology
spherical – coccoid
Colony morphology
fried egg morphology (Fig. 3)
Metabolism
fermentation of glucose; non-arginine-hydrolyzing, non-urea- hydrolyzing
Host
sheep and goats, wild ungulates including ibex, chamois
Habitat
eye, probably nasopharynx, possibly external ear canal
Disease(s)
Infectious Keratoconjunctivitis (IKC)
Pathogenicity
the only known pathogenicity factor is the adhesin LppS
Epidemiology
probably worldwide occurrence; transmission via close contact and flying insects
Diagnosis
PCR; cultivation (fastidious on primary isolation) and species identification by MALDI-ToF MS, serology or genetically
Fig. 1. Maximum likelihood tree showing the phylogenetic position of Mycoplasma conjunctivae HRC 581T within the Hyopneumoniae cluster of Mycoplasmataceae based on 16S rRNA gene sequences. The sequence of Mycoplasma synoviae WVU 1853T was used as out-group (Synoviae cluster). Numbers at nodes represent bootstrap confidence values (1000 replications). Only values > 80% are shown. Bar, number of substitutions per nucleotide position. Credits: Joachim Spergser (Vetmeduni Vienna)
CTTGCTGTGTGCCTAATACATGCATGTTGAACGGGATGTTTTAGTTTACTAAAACATTTAGTAGCGAATGGGTGAGTAACACGTACCTAACCTACCTTTAGGATTGGGATAACTACTGGAAACAGTAGCTAATACCGAATATAATATTTTTTCGCATGAAGAAATATAGAAAGGAGCCTTTAAAGCTTCACCTAGAAATGGGGGTGCGGAACATTAGTTAGTTGGTGAGGTAATGGCTCACCAAGACAATGATGTTTAGCGGGGCCAAGAGGTTGTACCGCCACACTGGGACTGAGATACGGCCCAGACTCCTACGGGAGGCAGCAGTAAGGAATTTTCCACAATGAGCGAAAGCTTGATGGAGCGACACAGCGTGCAGGATGAAATCCCTCGGGATGTAAACTGCTGTTATAAGGAAAGAAAAAATCAAATAGGAAATGATTTGATCTTGACGGTACCTTATTAGAAAGCGACGGCAAACTATGTGCCAGCAGCCGCGGTAATACATAGGTCGCAAGCGTTATCCGGAATTATTGGGCGTAAAGCGTCCGTAGGTTTTTTGTTAAGTTTAAGGTTAAATACTGAAGCTCAACTTCAGCCCGCTTTAGATACTGGCAAAATAGAATTATGAAGAGGTTAGCGGAATTCCTAGTGTAGCGGTGGAATGCGTAGATATTAGGAAGAACACCAATAGGCGAAGGCAGCTAACTGGTCATACATTGACACTAAGGGACGAAAGCGTGGGGAGCAAACAGGATTAGATACCCTGGTAGTCCACGCTGTAAACGATGATCATTAGTTGGTGGTATTAAATCACTAACACAGCTAACGCGTTAAATGATCCGCCTGAGTAGTATGCTCGCAAGAGTGAAACTTAAAGGAATTGACGGGAACCCGCACAAGCGGTGGAGCATGTGGTTTAATTTGAAGATACGCGTAGAACCTTACCCACTCTTGACATCCTTGCAAAGCTATAGAGATATAGTGGAGGCTAACAAGATGACAGATGGTGCATGGTTGTCGTCAGCTCGTGTCGTGAGATGTTAGGTTAAGTCCTGCAACGAGCGCAACCCCTTTCTTTAGTTACTAACGTGAAAGACGAGGACTCTAAAGATACTGCCTGTGTAAGCCGGAGGAAGGTGGGGACGACGTCAAATCATCATGCCTCTTACGAGTGGGGCAACACACGTGCTACAATGGCTACTACAAAGAGACGCAAGACGGTGACGTTAAGCAAATCTCAAAAAAGTAGTCCCAGTTCGGATTGAAGTCTGCAACTCGACTTCATGAAGTCGGAATCGCTAGTAATCGCAGATCAGCTACGCTGCGGTGAATACGTTCTCGGGTTTTGTACACACCGCCCGTCACACCATGGGAGTTGGTAATGCCCAAAGTCGGTGAGTTAACTTCGGAGACCATTGCCTAAGGCAGGACTGATGACTGGGGTGAAGTCGTAACAAGGT
Fig. 2. 16S rRNA gene sequence of Mycoplasma conjunctivae HRC 581T (Accession number: NR_044781)
Fig. 3. Colonies of Mycoplasma conjunctivae HRC 581Ton modified Friis’ agar after 6 days of incubation exhibiting characteristic fried egg morphology. Bar, 1 mm. Credits: Joachim Spergser (Vetmeduni Vienna)