Uptake and persistence of human associated Enterococcus in the mussel Mytilus edulis: relevance for faecal pollution source tracking.
OBJECTIVE
Micro-organisms and molecular markers for microbial source tracking (MST) in coastal waters are often present at low numbers, and often exhibit significant variability in time and space. In this study, we investigated the uptake, accumulation, and persistence of human associated Enterococcus in the mussel Mytilus edulis.


RESULTS
The human associated molecular markers esp in Enterococcus faecium, and M66 in Enterococcus faecalis were targetted by PCR in seawater and mussel samples from coastal sites affected by sewage contamination. Both native mussels and mussels transplanted from pristine to polluted sites were included. The results showed that the esp and M66 markers were often not detectable in seawater whereas mussels were enriched in the markers. Human associated E. faecalis accumulated rapidly in M. edulis, and reached maximum levels after 4-6 h with concentration 30-300 times greater than in the surrounding seawater. Enterococcus faecalis retained in M. edulis showed a survival comparable to planktonic E. faecalis in seawater with half lives of 30 and 22 h, respectively. Human associated markers remained detectable for 120 h in M. edulis after faecal contamination.


CONCLUSIONS
The study demonstrated that native and transplanted M. edulis can accumulate and retain human associated molecular markers relevant for MST.


CONCLUSIONS
Mussels should be considered as additional targets in MST studies in coastal waters.
Roslev
P
P
Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Aalborg, Denmark. pr@bio.aau.dk
Iversen
L
L
Sønderbo
H L
HL
Iversen
N
N
Bastholm
S
S
D000818:Animals; D002352:Carrier Proteins / Q000235:genetics; D015169:Colony Count, Microbial; D016983:Enterococcus; D013293:Enterococcus faecalis / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D016984:Enterococcus faecium / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D004784:Environmental Monitoring / Q000379:methods*; D005243:Feces / Q000382:microbiology*; D005819:Genetic Markers; D006801:Humans; D049880:Mytilus edulis / Q000382:microbiology*; D016133:Polymerase Chain Reaction; D012623:Seawater / Q000382:microbiology*; D029589:Seminal Plasma Proteins / Q000235:genetics; D014871:Water Microbiology
D002352:Carrier Proteins; D005819:Genetic Markers; C484958:SPESP1 protein, human; D029589:Seminal Plasma Proteins