Sentence:  Cultures taken from the jejunum yielded Monilia albicans , Pseudomonas pyocanea , <WSD>Aerobacter</WSD> aerogenes , and Streptococcus anhemolyticus . 
Meaning of the word marked with <WSD> tags:  a species of Gram-negative aerobic bacteria that produce gas and acid from sugars and are sometimes involved in the souring of milk