No, Mycobacterium phlei is not known to form capsules. Capsule formation is more commonly associated with certain pathogenic bacteria to help evade the host immune response. Mycobacterium phlei is a non-pathogenic soil bacteria and does not typically form capsules.
Mycobacterium phlei is a non-fastidious organism that is commonly found in soil and water. It is not commonly grown on Eosin Methylene Blue (EMB) agar, as EMB agar is more selective for gram-negative enteric bacteria. Instead, Mycobacterium phlei is typically cultured on media specifically designed for mycobacteria, such as Middlebrook agar or Lowenstein-Jensen agar.
Although mycoplasma lack a cell wall and therefore test gram negative, they are considered to be descendents of 'nonsporulating and endospore forming gram-positive bacteria' (Madigan et al., 2009), such as Lactobacilli, Bacilli and Streptococci, (Dandekar et al., 2002), which have lost their cell wall. Mycoplasmas are therfore classed as gram- positive bacteria. This is supported by ribosomal RNA and DNA analysis.