Cells are Gram-stain-positive at the early stages of growth
but are not clearly stained at the late exponential to
stationary phase.
They are non-spore-forming, non-motile ,
rods, 0.562–4 mm, and occur singly, in pairs or in short chains. Catalase-negative. Colonies develop well on MRS agar plates under both anaerobic and aerobic (air) conditions.
Colonies on MRS agar are yellowish-white, smooth and approx. 1–2 mm in diameter after incubation for 2 days at 30 ºC.