Table 4.

Comparison of peptidase/protease tests used in systems for identification of gram-positive bacteria

Substrate specificityIdentification systema
IdentifiesMicrococcaceae andStreptococcaceaeIdentifiesMicrococcaceaeIdentifies Streptococcaceae
MS GPMS Rapid GPVitek GPIPasco GP IDAPI Staph IDGeary et al. (86)Kloos and Bannerman (129)API Staph ID 32StaphZymRapID STRRapid ID 32 StrepAPI 20 Strep
l-AlanineAMC
Alanyl-phenylalanine-proline+
l-ArginineAMCβNAβNA
l-CitrullineAMC
α-l-Glutamic acidAMC
Glycyl-tryptophan+
HydroxyprolineβNA
LeucineAMCβNA
l-LysineAMCβNA
MethionineAMC
l-PhenylalanineAMC
l-Pyroglutamic acidAMCβNA+
l-PyrrolidoneβNAβNAβNA+βNAβNA
l-TyrosineAMCβNA
No. of tests1100100221432
  • a For an explanation of the identification systems, see Table 1, footnote a. AMC, 7-amido-4-methylcoumarin; βNA, β-naphthylamine; +, proprietary synthetic moiety.