OP50.1

[fodoran at FALCO.GEOBIO.ELTE.HU]

Dear Bandy,

I made a terrible mistake! By written RESISTANT instead of SENSITIVE!!!

The OP50 was SENSITIVE not resistant to all antibiotics tested.
I may have a starting Alzheimer ... Sorry.

Andras

On 26 Aug 1997, Tritech Research wrote:

> fodoran at FALCO.GEOBIO.ELTE.HU,Internet writes:
> 			ANTIBIOTICS SENSITIVITY OF OP50.
> 
> Csaba Bognar(2), Tibor Vellai(1) and Andras Fodor(1),
> 1. 	Dept. Genetics, Eotvos University, H-1088 Budapest, Muzeum krt. 4/A,
> 	Hungary
> 2. 	Bela Johann National Institute of Public Health in Hungary, Department
> 	of Bacteriology, (OKI), H-1097 Budapest, Gyali ut 2-6, Hungary.
> 
> E. coli OP50 is used practically by everybody in the C. elegans Community
> as natural food for C.elegans. Our substrain what we use was kindly
> provided by Ian Hope in 1995. We have tested its antibiotics sensitivity,
> by the paper disc method routinly used the OKI. We used 30 ug/ml of each
> antibiotics tested. The filter paper discs are out on the center of the
> NGM plate seeded by OP bacteria. An inhibition zone develops, if the
> antibiotics is effective against the baccteria under test. Conventionally,
> if the diameter oif the inhibition zone is smaller then 2 cm, we conclude
> that the bacteria is resistant to the antibiotics tested. We tested 24
> antibiotics, as follows:
> 
> gentamycin; tobramycin; sumetrolim; chloramphenicol; tetracycline;
> ampicyllin; karbenicillin; cefalexine; cefamandol; cefuroxime; amykacin;
> netylmycine; azlocilline; mezlocillin; ceftriaxone; cefatoxim;
> cefroperazon; ofloxacin; pestloxacin; cyprofloxacim; ceftazidin; cefaclor;
> augmentin; and kanamycin. (Some of the names are probably written in very
> Hungarian; we promise the correct them in the Newsletter article).
> 
> Well, we found that OP50 was completely resistant to all these
> antibiotics.
> 
> I hope these data help Liz and other fellow Colleauges to work with OP50.
> 
> Faithfully yours,
> 
> Andras and his gang.   
> ------------------
> This sounds very strange to me (?)  If true, it would be one of the heartiest
> (and most dangerous) strains of bacteria in the world (?)  My experience
> with OP50 is that it is killed easily by Amp and Str.  2 cm requires a lot
> of diffusion.  Might this be too much to ask from the filter disks?  Is it
> possible that doing the test on NGM with a high agar or agarose content is
> limiting diffusion?  Could this possibly be a contaminating yeast?
> 
> Curious,
> Andy Papp
> tritech_research at LAMG.COM
> 

========================================================================
Dr. Andras Fodor			e-mail: fodoran at ludens.elte.hu	
Associate Professor			or:	fodoran at falco.elte.hu
Eotvos University			Phone:	+36.1.266.1296
Department of Genetics				+36.1.267.5444 ext. 2348
Budapest, Muzeum krt. 4/A		FAX:	+36.1.266.2694
H-1088 HUNGARY
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