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bacterium(maybe not) identification problem - (Mar/08/2014 )

hello everyone
Recently I got an isolate from air sample collected from a henhouse. But I can’t identify it.
It forms small white round clone on blood agar after incubated at 37℃ for 15h, and grows to large clone about 4-6mm for 48h. it is Gram+ , elliptical shape, larger than Staphylococcus and Enterococcus I used to observe.
I used the bacteria DNA extraction kit to prepare DNA and amplified 16S rDNA gene, but I couldn’t get a band! Then I tried it again with an Enterococcus faecalis as positive control, the E. faecalis had the correct band but the isolate didn’t.
Other informations: I did the antibiotic resistance phenotype detection of this isolate, it resist to almost all antibiotics except polymyxinB. The catalase test is positive.
The colonial morphology does not look like fungus, so I don’t know why I can’t get a 16 S band. I hope that someone can give me advices about how to identify the isolate or what it might be.

Attached Image


Looks like a yeast, which would be catalase + and Gram+ ( though not a real Gram stain, as it isn't the right things staining for this process).


Some of them seems budding -> yeast

Please, always indicate magnification in microscope pics.

-El Crazy Xabi-

Yeast-like fungi are commonly found in bird droppings.   Please use appropriate aseptic technique as such materials have been associated with outbreaks of histoplasmosis (

-Phil Geis-