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Identifying unknown

About microscopic forms of life, including Bacteria, Archea, protozoans, algae and fungi. Topics relating to viruses, viroids and prions also belong here.

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Identifying unknown

Postby mccullyj » Fri Apr 24, 2009 10:22 pm

I need to identify an unknown from the environment, but am having trouble finding somewhere to start. I have quite a bit of information. Colonies are cream colored. It is gram positive. It grew at high concentrations of sodium chloride (.5%,2%,%5,20%). It grew at 4 degree celsius and 25 degree celsius. Citrate test positive, it grew only at a 7pH. Grew on plates with glucose, glucose and amino acids, glucose, amino acids and yeast extract, and just amino acids. It grew without oxygen and with oxygen. It grew on MacConkey agar but not on mannitol salts agar. No amylase. It is a fermenter. It produced acid but no gas in a phenol-red with glucose containing a Durham tube. MR+/VP-. In a triple sugar iron test the butt was yellow, slant pink and produce minimal gas. Indole test positive. It reduced nitrate. Oxidase negative, catalase positive but weak, coagulase negative, b hemolitic and had motility. Motility test done in motility medium. If anyone has any suggestions on what this is or can direct me to a website that can help, that would be much appreciated.
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Postby Cat » Sat May 02, 2009 5:33 pm

Why are performing a bunch of test in no particular order? Don't you have a scheme? And why are you missing important information - is it coccus or bacillus?

You also say that it is weekly catalase positive. I would redo the test (you sure that your culture is pure?) because your bacteria is indole positive. Indole test usually performed on the gram negative bacteria. The only gram positive bacteria (that I know of) that is indole positive is Enterococcus faecalis (also called Streptococcus faecalis) and as other Strep bacteria they are catalase negative.

However, if your bacteria are bacilli then your gram stain is most likely is wrong...

Here are some ID schemes: ... ;init:.jpg ... ;init:.jpg
King Cobra
King Cobra
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