title: Evidence of global chlorophyll d.
abstract: Although analyses of chlorophyll d (Chl d)-dominated oxygenic photosystems have been conducted since their discovery 12 years ago, Chl d distribution in the environment and quantitative importance for aquatic photosynthesis remain to be investigated. We analyzed the pigment compositions of surface sediments and detected Chl d and its derivatives from diverse aquatic environments. Our data show that the viable habitat for Chl d-producing phototrophs extends across salinities of 0 to 50 practical salinity units and temperatures of 1 degrees to 40 degrees C, suggesting that Chl d production can be ubiquitously observed in aquatic environments that receive near-infrared light. The relative abundances of Chl d derivatives over that of Chl a derivatives in the studied samples are up to 4%, further suggesting that Chl d-based photosynthesis plays a quantitatively important role in the aquatic photosynthesis.
authors.affiliation: Institute for Research on Earth Evolution, Japan Agency for Marine-Earth Science and Technology, Yokosuka 237-0061, Japan. chiro@jamstec.go.jp
authors.forename: Y
authors.initials: Y
authors.lastname: Kashiyama
authors.forename: H
authors.initials: H
authors.lastname: Miyashita
authors.forename: S
authors.initials: S
authors.lastname: Ohkubo
authors.forename: N O
authors.initials: NO
authors.lastname: Ogawa
authors.forename: Y
authors.initials: Y
authors.lastname: Chikaraishi
authors.forename: Y
authors.initials: Y
authors.lastname: Takano
authors.forename: H
authors.initials: H
authors.lastname: Suga
authors.forename: T
authors.initials: T
authors.lastname: Toyofuku
authors.forename: H
authors.initials: H
authors.lastname: Nomaki
authors.forename: H
authors.initials: H
authors.lastname: Kitazato
authors.forename: T
authors.initials: T
authors.lastname: Nagata
authors.forename: N
authors.initials: N
authors.lastname: Ohkouchi
mesh_terms: D002734:Chlorophyll / Q000032:analysis* / Q000378:metabolism*; D000458:Cyanobacteria / Q000254:growth & development / Q000378:metabolism*; D017753:Ecosystem; D005618:Fresh Water / Q000737:chemistry; D019015:Geologic Sediments / Q000737:chemistry*; D010788:Photosynthesis; D052817:Phototrophic Processes; D054712:Salinity; D012623:Seawater / Q000737:chemistry; D013696:Temperature; D014867:Water / Q000737:chemistry
chemical_list: D014867:Water; D002734:Chlorophyll; C107509:chlorophyll d