Pelczaria aurantia gen. nov., sp. nov., a newly described orange-colored bacterium.

An organism from a goldfish aquarium, isolated on barbital medium, was found to be a Gram-positive coccus which divided in alternating planes, often appearing as a doublet or as a tetrad with adjacent sides flattened. It grew well, although slowly, on rich solid medium (LB agar) and in liquid brain-heart infusion at room temperature (ca. 22 degrees C); growth was slower and less extensive at 30 degrees C or 37 degrees C. No growth was seen at 4-5 degrees C or at 42 degrees C. It withstands brief exposure to ultraviolet radiation. Its growth was inhibited by low levels (0.1 unit/ml) of penicillin but was unaffected by levels of acetazolamide in excess of 1 mg/ml, indicating that it lacks carbonic anhydrase. Acid was not produced from glucose, maltose, mannose, lactose, or sucrose and only weakly, if at all, from fructose. Its DNA has a G + C mol percent of 59 measured chromatographically and neither the DNA nor rRNA from the organism hybridized with DNA from any organism that seemed related on morphological or other bases. Thin-layer chromatography of chloroform:methanol extracts of the organism show that it contains phosphatidyl choline, phosphatidyl ethanolamine, and phosphatidyl glycerol. Cell-wall preparations contain glutamic acid, serine, histidine, lysine, and alanine in the ratio of 1:1:1:1:8. Colonies were red-orange in color due, in larger measure, to a carotenoid tentatively identified as rhodopin. The organism was named Pelczaria aurantia.