North Pond, mid-Atlantic ridge crust, environmental amplicon tag sequencing

North Pond is a sediment pond located on young ridge flank oceanic crust on the mid-Atlantic ridge, overlaying permeable basaltic basement which hosts a cold, oligotrophic aquifer. Mineral colonization experiments consisting of sterile crushed rocks of different lithologies were installed in CORK subsurface observatory systems at North Pond in 2011 during IODP X336, and recovered in 2017. Upon recovery, we carried out activity assays to use with a fluorescent labelling technique called BONCAT, which allows individual active cells to be sorted and separated from the bulk community. We will carry out amplicon sequencing of the bulk and active microbial communities which have colonized the minerals incubated in the North Pond crustal subsurface. These results will be valuable to understanding microbial processes of assembly, selection and activity in the subsurface with respect to different mineral types. These results will be compared to those from other sites globally to contribute to understanding whether the crustal subsurface is composed of ubiquitous generalists, or whether there is an endemic crustal microbiome of specialists in the North Pond subsurface. Lead PI, Jackie Goordial.