title: Amplicon of human oral metagenome: adult
design: This study recruited newly diagnosed pulmonary tuberculosis (PTB) patients and their close contacts from the Fifth Affiliated Hospital of Sun Yat-sen University, categorizing them into BC, BN, LTBI, and HC groups. Oropharyngeal swab samples were collected before daily activities, stored at -80C, and processed for DNA extraction using a Bacterial DNA Rapid Extraction Kit. For sequencing, the integrity and purity of extracted DNA were verified, followed by PCR amplification with barcode primers. PCR products underwent equal-mass mixing, purification, and library construction using the NEBNext Ultra DNA Library Prep Kit for Illumina, creating a biological sample biobank. Sequencing was performed via Illumina nova PE274, with data processed for quality control, chimera removal, and OTU clustering. Diversity, microbial composition, and significant species differences were analyzed, and subgroup analysis investigated TB severity's impact on oropharyngeal microbiota.