This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bacterial infections, Subject name: Dental
[{'content': 'All are true about propionibacterium acne except \nSelect and explain. \nA. Normal flora of skin, B. Gram negative, C. Can be found in GIT, D. Causes acne vulgaris', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Propionibacterium acnes (P. acnes) * Gram +ve anaerobic rod, resident flora in follicle but acne patients with higher concentration * Naturally produces porphyrins (coproporphyrin III), which is the target of light-based acne therapy * Secretes lipases which cleave lipids in sebum into pro-inflammatory free fatty acids (FFAs), which are both comedogenic and chemotactic * Binds/activate toll-like receptor 2 (TLR2) * Causes Acne vulgaris. Ref:- Sima Jain; pg num:- 96', 'role': 'assistant'}]