The potential role of arginine in competitiveness and functionality of coagulase-negative staphylococci during meat fermentation

The capacity for arginine metabolism during meat fermentation offers a potential bonus in fitness to coagulase-negative staphylococci (CNS) in the absence of carbohydrates, as is particularly so for the arginine deiminase (ADI) pathway. An alternative is provided by the nitric oxide synthase (NOS) enzyme, which converts arginine into citrulline and nitrogen oxide (NO). Since NO causes colour-stabilizing nitrosylation of myoglobine, this pathway could potentially be used for the generation of nitrosomyoglobine in clean label products without added nitrate and/or nitrite. A genotypic and physiological screening of 88 CNS strains indicated that active ADI machinery is often found in this CNS group, although in a strain-specific manner. In contrast, phenotypic NOS-like activity was only present in one of the strains (Staphylococcus haemolyticus G110), although the genetic potential for NOS was widespread among CNS strains. Attempts to express NOS activity in some of the latter strains were unsuccessful, suggesting that the genetic potential for NOS is not commonly expressed by CNS. Both ADI and NOS kinetics were investigated in a meat simulation medium, indicating the need for sufficient oxygen for NOS activity. The use of NOS-positive CNS cultures as a curing alternative in fermented meats is thus not clear-cut.

Jaar van publicatie:2014

Trefwoorden:Meat fermentation, Coagulase-negative staphylococci, Arginine deiminase, nitric oxide synthase, Colour