TY - JOUR
T1 - A ubiquitous mobile genetic element changes the antagonistic weaponry of a human gut symbiont
AU - Sheahan, Madeline L.
AU - Flores, Katia
AU - Coyne, Michael J.
AU - García-Bayona, Leonor
AU - Chatzidaki-Livanis, Maria
AU - Holst, Andrea Q.
AU - Smith, Rita C.
AU - Sundararajan, Anitha
AU - Barquera, Blanca
AU - Comstock, Laurie E.
PY - 2024
Y1 - 2024
N2 - DNA transfer is ubiquitous in the human gut microbiota, especially among species of the order Bacteroidales. In silico analyses have revealed hundreds of mobile genetic elements shared between these species, yet little is known about the phenotypes they encode, their effects on fitness, or pleiotropic consequences for the recipient's genome. In this work, we show that acquisition of a ubiquitous integrative conjugative element (ICE) encoding a type VI secretion system (T6SS) shuts down the native T6SS of Bacteroides fragilis. Despite inactivating this T6SS, ICE acquisition increases the fitness of the B. fragilis transconjugant over its progenitor by arming it with the new T6SS. DNA transfer causes the strain to change allegiances so that it no longer targets ecosystem members with the same element yet is armed for communal defense.
AB - DNA transfer is ubiquitous in the human gut microbiota, especially among species of the order Bacteroidales. In silico analyses have revealed hundreds of mobile genetic elements shared between these species, yet little is known about the phenotypes they encode, their effects on fitness, or pleiotropic consequences for the recipient's genome. In this work, we show that acquisition of a ubiquitous integrative conjugative element (ICE) encoding a type VI secretion system (T6SS) shuts down the native T6SS of Bacteroides fragilis. Despite inactivating this T6SS, ICE acquisition increases the fitness of the B. fragilis transconjugant over its progenitor by arming it with the new T6SS. DNA transfer causes the strain to change allegiances so that it no longer targets ecosystem members with the same element yet is armed for communal defense.
U2 - 10.1126/science.adj9504
DO - 10.1126/science.adj9504
M3 - Journal article
C2 - 39446952
SN - 0036-8075
VL - 386
SP - 414
EP - 420
JO - Science
JF - Science
IS - 6720
ER -