Gram positive: Most Streptococci, Enterococcus faecalis, Staph aureus (MSSA)
Gram negative: Many Enterobacteriaceae, Neisseria spp. Haemophilus, Moraxella, Pasteurella
Anaerobes: Bacteroides fragilis, Prevotella, non-difficile Clostridia, Peptostreptococci, Actinomyces