This study investigates the microbial composition of atherosclerotic plaques, oral, and gut microbiotas in patients with atherosclerosis. Using 454 pyrosequencing of 16S rRNA genes, researchers analyzed 15 patients with atherosclerosis and 15 healthy controls. They found that bacterial DNA was present in atherosclerotic plaques, with the amount correlating with the number of leukocytes. Chryseomonas (now classified as Pseudomonas luteola) was detected in all atherosclerotic plaque samples, while Veillonella and Streptococcus were common in the oral cavity. The combined abundances of Veillonella and Streptococcus in atherosclerotic plaques correlated with their abundance in the oral cavity. Several bacterial taxa in the oral cavity and gut correlated with plasma cholesterol levels. These findings suggest that bacteria from the oral cavity and possibly the gut may be linked to atherosclerosis markers. The study also found that the oral microbiota was dominated by Firmicutes, followed by Bacteroidetes, Actinobacteria, Fusobacteria, and Bacteroidetes. The gut microbiota showed similar phylum distribution between patients and controls, but certain OTUs were more abundant in the gut. The atherosclerotic plaque microbiota contained bacteria from different phyla, with some OTUs shared between the plaque and oral or gut samples. The abundance of certain bacteria, such as Fusobacterium, correlated with cholesterol and LDL cholesterol levels, while Streptococcus correlated with HDL cholesterol and ApoAI levels. Neisseria was negatively correlated with these markers. The study also found that bacteria in the atherosclerotic plaque could originate from the oral cavity and gut. The presence of bacteria in atherosclerotic plaques may be due to phagocytosis by macrophages at epithelial linings. The study suggests that the oral and gut microbiotas may contribute to atherosclerosis by affecting inflammatory status and lipid metabolism. The findings highlight the potential role of the oral and gut microbiotas in atherosclerosis and suggest that further research is needed to explore how specific bacteria may contribute to the development and progression of atherosclerosis.This study investigates the microbial composition of atherosclerotic plaques, oral, and gut microbiotas in patients with atherosclerosis. Using 454 pyrosequencing of 16S rRNA genes, researchers analyzed 15 patients with atherosclerosis and 15 healthy controls. They found that bacterial DNA was present in atherosclerotic plaques, with the amount correlating with the number of leukocytes. Chryseomonas (now classified as Pseudomonas luteola) was detected in all atherosclerotic plaque samples, while Veillonella and Streptococcus were common in the oral cavity. The combined abundances of Veillonella and Streptococcus in atherosclerotic plaques correlated with their abundance in the oral cavity. Several bacterial taxa in the oral cavity and gut correlated with plasma cholesterol levels. These findings suggest that bacteria from the oral cavity and possibly the gut may be linked to atherosclerosis markers. The study also found that the oral microbiota was dominated by Firmicutes, followed by Bacteroidetes, Actinobacteria, Fusobacteria, and Bacteroidetes. The gut microbiota showed similar phylum distribution between patients and controls, but certain OTUs were more abundant in the gut. The atherosclerotic plaque microbiota contained bacteria from different phyla, with some OTUs shared between the plaque and oral or gut samples. The abundance of certain bacteria, such as Fusobacterium, correlated with cholesterol and LDL cholesterol levels, while Streptococcus correlated with HDL cholesterol and ApoAI levels. Neisseria was negatively correlated with these markers. The study also found that bacteria in the atherosclerotic plaque could originate from the oral cavity and gut. The presence of bacteria in atherosclerotic plaques may be due to phagocytosis by macrophages at epithelial linings. The study suggests that the oral and gut microbiotas may contribute to atherosclerosis by affecting inflammatory status and lipid metabolism. The findings highlight the potential role of the oral and gut microbiotas in atherosclerosis and suggest that further research is needed to explore how specific bacteria may contribute to the development and progression of atherosclerosis.