mothers may be a source of avirulent E. faecium isolates to the
newborns.”
E. faecium NRRL B-2354 (ATCC 8459, NCIMB 2699) Uses
in the Food Industry
Originally, this organism was called Micrococcus freudenreichii
ATCC 8459. The taxonomic name M. freudenreichii was
eventually dropped32. Previously, it was “species incertae sedis.” 33
It is my understanding that the strain was dropped because
the G+C content differed too much from other members of
the genus Micrococcus. The strain was later called (unofficially)
be used to enhance cheese flavor development, including
Micrococcus sp. ATCC 8459 and cited the work of Alford
and Frazer, 47 who used M. freudenreichii to accelerate the
ripening of Cheddar cheese.
4. M. freudenreichii has been used for at least 64 years by
microbiologists as a nonpathogenic surrogate organism
in place of pathogens to validate thermal processes of
foods beginning, apparently with Speck48 with regard to
pasteurized milk and ice cream mix, Speck and Lucas49 with
chocolate milk and Collins et al. 50 with pasteurized milk.
“...food manufacturers should not be discouraged from the use of E. faecium
NRRL B-2354.”
Pediococcus sp. NRRL B2354 by USDA3 until the early part
of the past decade, when the ATCC began to refer to it as E.
faecium ATCC 8459. Sometime late in the last decade, ATCC
elected to call all strains of E. faecium BSL2 organisms. This
is unfortunate for the food industry for a variety of reasons:
ATCC 8459 has been used as an adjunct starter culture for
cheese manufacture34 and also as a surrogate in place of food
pathogens (like Salmonella and L. monocytogenes) to validate
the safety of thermal processing to kill pathogens in a variety
of foods. In addition, this same strain, also known as NCIB
2699, was noted to produce a bacteriocin active against L.
monocytogenes, 35, 36 thus showing potential for further use of the
organism in the manufacture of safe foods.
I have seen no evidence in the literature to suggest this
particular strain represents a health risk in food, but much
evidence of beneficial use in food development and research
for the following reasons.
1. The microbe formerly known as M. freudenreichii (not
necessarily ATCC 8459) was commonly found in foods in
the past. Consequently, if this microbe was a pathogen, it is
likely that we would have discovered it previously. The use
of M. freudenreichii (not necessarily ATCC strain 8459) as an
adjunct starter culture was also previously documented. 37–42
2. The microbe (not necessarily ATCC 8459) has been shown
to contribute significantly to the ripening process of various
cheeses. 38, 43 Fox and Tobin43 stated that “adjunct bacteria,
including mesophilic and thermophilic lactobacilli,
M. freudenreichii and Pediococcus pentosaceus have shown some
promise in the manufacture of low-fat cheese with reduced
defects and improved flavor.” Please note: Adjunct bacteria
are deliberately added to cheese.
3. Three patents have been issued for its deliberate use in
cheese manufacture for the purpose of enhancing the
flavor as adjunct cultures. 34, 44–47 Luksas44 states that the
cheese is “Inoculated with a nontoxic Micrococcus such as…
Micrococcus freudenreichii ATCC 407 or 8459.” This suggests
an industrial food use of the specific strain for the last 40
years. Bhomick and Marth46 screened cultures for their
proteolytic activity to find Micrococcus cultures that may
Other researchers have used this organism to study the heat
resistance in concentrated ultrafiltered milk retentates, 51
juice products, 3 microwave processing of a variety of fluids, 52
apple cider, 53 oven treatment of wheat-based products, 6, 7
cooking of ground beef11 and almond roasting. 54
Implication of Enterococcus spp. in Human
Foodborne Illness: Virulence Factors
