title: Meconium microbiome analysis identifies bacteria correlated with premature birth.
abstract: BACKGROUND
  Preterm birth is the second leading cause of death in children under the age of five years worldwide, but the etiology of many cases remains enigmatic. The dogma that the fetus resides in a sterile environment is being challenged by recent findings and the question has arisen whether microbes that colonize the fetus may be related to preterm birth. It has been posited that meconium reflects the in-utero microbial environment. In this study, correlations between fetal intestinal bacteria from meconium and gestational age were examined in order to suggest underlying mechanisms that may contribute to preterm birth.
  
  
  METHODS
  Meconium from 52 infants ranging in gestational age from 23 to 41 weeks was collected, the DNA extracted, and 16S rRNA analysis performed. Resulting taxa of microbes were correlated to clinical variables and also compared to previous studies of amniotic fluid and other human microbiome niches.
  
  
  RESULTS
  Increased detection of bacterial 16S rRNA in meconium of infants of <33 weeks gestational age was observed. Approximately 61·1% of reads sequenced were classified to genera that have been reported in amniotic fluid. Gestational age had the largest influence on microbial community structure (R = 0·161; p = 0·029), while mode of delivery (C-section versus vaginal delivery) had an effect as well (R = 0·100; p = 0·044). Enterobacter, Enterococcus, Lactobacillus, Photorhabdus, and Tannerella, were negatively correlated with gestational age and have been reported to incite inflammatory responses, suggesting a causative role in premature birth.
  
  
  CONCLUSIONS
  This provides the first evidence to support the hypothesis that the fetal intestinal microbiome derived from swallowed amniotic fluid may be involved in the inflammatory response that leads to premature birth.
authors.affiliation: Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, United States of America.
authors.forename: Alexandria N
authors.initials: AN
authors.lastname: Ardissone
authors.affiliation: Department of Pediatrics, University of Florida, Gainesville, Florida, United States of America.
authors.forename: Diomel M
authors.initials: DM
authors.lastname: de la Cruz
authors.affiliation: Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, United States of America.
authors.forename: Austin G
authors.initials: AG
authors.lastname: Davis-Richardson
authors.affiliation: Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, United States of America.
authors.forename: Kevin T
authors.initials: KT
authors.lastname: Rechcigl
authors.affiliation: Department of Pediatrics, University of Florida, Gainesville, Florida, United States of America.
authors.forename: Nan
authors.initials: N
authors.lastname: Li
authors.affiliation: Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, United States of America.
authors.forename: Jennifer C
authors.initials: JC
authors.lastname: Drew
authors.affiliation: Department of Pediatrics, University of Florida, Gainesville, Florida, United States of America.
authors.forename: Roberto
authors.initials: R
authors.lastname: Murgas-Torrazza
authors.affiliation: Department of Pediatrics, University of Florida, Jacksonville, Florida, United States of America.
authors.forename: Renu
authors.initials: R
authors.lastname: Sharma
authors.affiliation: Department of Pediatrics, University of Florida, Jacksonville, Florida, United States of America.
authors.forename: Mark L
authors.initials: ML
authors.lastname: Hudak
authors.affiliation: Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, United States of America.
authors.forename: Eric W
authors.initials: EW
authors.lastname: Triplett
authors.affiliation: Department of Pediatrics, University of Florida, Gainesville, Florida, United States of America.
authors.forename: Josef
authors.initials: J
authors.lastname: Neu
mesh_terms: D000653:Amniotic Fluid / Q000382:microbiology; D001419:Bacteria / Q000378:metabolism*; D044822:Biodiversity; D015415:Biomarkers / Q000378:metabolism; D015169:Colony Count, Microbial; D015986:Confounding Factors, Epidemiologic; D036861:Delivery, Obstetric; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D018836:Inflammation Mediators / Q000378:metabolism; D008470:Meconium / Q000382:microbiology*; D064307:Microbiota; D011247:Pregnancy; D047928:Premature Birth / Q000382:microbiology*; D000067616:S100A12 Protein / Q000378:metabolism
chemical_list: D015415:Biomarkers; D018836:Inflammation Mediators; D000067616:S100A12 Protein; C090441:S100A12 protein, human