title: Bacterial communities in semen from men of infertile couples: metagenomic sequencing reveals relationships of seminal microbiota to semen quality.
abstract: Some previous studies have identified bacteria in semen as being a potential factor in male infertility. However, only few types of bacteria were taken into consideration while using PCR-based or culturing methods. Here we present an analysis approach using next-generation sequencing technology and bioinformatics analysis to investigate the associations between bacterial communities and semen quality. Ninety-six semen samples collected were examined for bacterial communities, measuring seven clinical criteria for semen quality (semen volume, sperm concentration, motility, Kruger's strict morphology, antisperm antibody (IgA), Atypical, and leukocytes). Computer-assisted semen analysis (CASA) was also performed. Results showed that the most abundant genera among all samples were Lactobacillus (19.9%), Pseudomonas (9.85%), Prevotella (8.51%) and Gardnerella (4.21%). The proportion of Lactobacillus and Gardnerella was significantly higher in the normal samples, while that of Prevotella was significantly higher in the low quality samples. Unsupervised clustering analysis demonstrated that the seminal bacterial communities were clustered into three main groups: Lactobacillus, Pseudomonas, and Prevotella predominant group. Remarkably, most normal samples (80.6%) were clustered in Lactobacillus predominant group. The analysis results showed seminal bacteria community types were highly associated with semen health. Lactobacillus might not only be a potential probiotic for semen quality maintenance, but also might be helpful in countering the negative influence of Prevotella and Pseudomonas. In this study, we investigated whole seminal bacterial communities and provided the most comprehensive analysis of the association between bacterial community and semen quality. The study significantly contributes to the current understanding of the etiology of male fertility.
authors.affiliation: Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, Taiwan; Department of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan; Department of Obstetrics and Gynecology, Hsinchu Mackay Memorial Hospital, Hsinchu, Taiwan; Mackay Junior College of Medicine, Nursing and Management, Taipei, Taiwan; Department of Medicine, Mackay Medical College, New Taipei City, Taiwan.
authors.forename: Shun-Long
authors.initials: SL
authors.lastname: Weng
authors.affiliation: Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, Taiwan.
authors.forename: Chih-Min
authors.initials: CM
authors.lastname: Chiu
authors.affiliation: Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, Taiwan.
authors.forename: Feng-Mao
authors.initials: FM
authors.lastname: Lin
authors.affiliation: Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, Taiwan.
authors.forename: Wei-Chih
authors.initials: WC
authors.lastname: Huang
authors.affiliation: Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, Taiwan.
authors.forename: Chao
authors.initials: C
authors.lastname: Liang
authors.affiliation: Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, Taiwan.
authors.forename: Ting
authors.initials: T
authors.lastname: Yang
authors.affiliation: Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, Taiwan.
authors.forename: Tzu-Ling
authors.initials: TL
authors.lastname: Yang
authors.affiliation: Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, Taiwan.
authors.forename: Chia-Yu
authors.initials: CY
authors.lastname: Liu
authors.affiliation: Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, Taiwan.
authors.forename: Wei-Yun
authors.initials: WY
authors.lastname: Wu
authors.affiliation: Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, Taiwan; Health GeneTech Corporation, Taoyuan, Taiwan.
authors.forename: Yi-An
authors.initials: YA
authors.lastname: Chang
authors.affiliation: Graduate Institute of Biomedical Informatics, Taipei Medical University, Taipei, Taiwan.
authors.forename: Tzu-Hao
authors.initials: TH
authors.lastname: Chang
authors.affiliation: Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu, Taiwan; Department of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan; Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung, Taiwan; Center for Bioinformatics Research, National Chiao Tung University, HsinChu, Taiwan.
authors.forename: Hsien-Da
authors.initials: HD
authors.lastname: Huang
mesh_terms: D000328:Adult; D001419:Bacteria / Q000235:genetics; D044822:Biodiversity; D015415:Biomarkers / Q000378:metabolism; D016022:Case-Control Studies; D016000:Cluster Analysis; D003710:Demography; D006801:Humans; D007248:Infertility, Male / Q000382:microbiology*; D008297:Male; D056186:Metagenomics; D064307:Microbiota / Q000235:genetics*; D008875:Middle Aged; D025341:Principal Component Analysis; D012661:Semen / Q000382:microbiology*; D055101:Semen Analysis; D017422:Sequence Analysis, DNA; D013045:Species Specificity
chemical_list: D015415:Biomarkers