Phage contamination

Phage contamination of some sections of the I.M.A.G.E clone bank

(Joint statement of the UK HGMP Resource Centre, Hinxton and the Resource Centre/Primary Database (RZPD), Germany)


The I.M.A.G.E. clone bank and the associated EST database have become essential tools for the research community, and we at the Resource Centre of the German Human Genome Project, RZPD, and at the UK HGMP Resource Centre Hinxton are committed to maintaining and extending their utility. We have recently identified bacteriophage contamination in a proportion of the I.M.A.G.E. clone bank, apparently coliphage T1-related in most if not all cases. The fact that the same sections are contaminated in both of our laboratories strongly suggests that the problem originated elsewhere. Phage T1 contamination can spread rapidly to other E.coli cultures. We have put procedures in place to minimise the chance of transfer of phage contamination to users through I.M.A.G.E. shipments from our centres. We believe that as users of I.M.A.G.E. clones you should be aware of the possibility of phage contamination and apply appropriate microbiological practices to ensure that your labs remain contamination free. We have withdrawn badly contaminated sections of the bank from distribution. All other clone requests will be tested for phage contamination before shipment, and users will be notified of the result. Clones which test negative for phage will be shipped directly. Users will be notified of phage contamination, and must confirm their willingness to accept contaminated clones before shipment.


Chris Mundy DPhil 
Biology Manager
UK HGMP Resource Centre
Dr. Guenther Zehetner
Scientific Director
Resource Centre/Primary Database of the German Human
Genome Project at the Max-Planck-Institut for 
Molecular Genetics


Statement from the I.M.A.G.E. Consortium  -  25 Sep 1998


The I.M.A.G.E. Consortium distributors, in parallel with LLNL, have completed extensive testing on a subset of plates.  This testing procedure involved lysis as well as PCR and sequencing assays to determine the extent of the phage contamination.  Results suggest that the master set of plates is free from contamination, and new replicas of all affected plates will be made available to the distributors as soon as possible.  Each laboratory has introduced more stringent sterility procedures to avoid the recurrence of this problem, and in addition, we are using a host strain of phage-resistant E.coli wherever possible. As always, we encourage all researchers to use caution when working with bacterial clones from any source, and we regret any inconvenience this has caused.


Reiteration of HGMP policy


1) All new I.M.A.G.E. plates received will be tested for Phage contamination. Any heavily contaminated plates/sections will be withdrawn

2) All I.M.A.G.E. clone orders will be tested, using a Top Agarose assay.

3) If negative with our assay the clone(s) will dispatched directly to the user. It should be noted that even clones which have tested negative for phage should still be handled with care as no phage assay can be guaranteed to be 100% accurate.

4) If the clone tests positive the user will be informed, and the clone will only be despatched following confirmation from the user that their laboratory wishes to receive this clone.


Document Date August 2000