An ectobiont-bearing foraminiferan, Bolivina pacifica, that inhabits microxic pore waters: cell-biological and paleoceanographic insights.
Environ Microbiol
; 12(8): 2107-19, 2010 Aug.
Article
em En
| MEDLINE
| ID: mdl-21966906
ABSTRACT
The presence of tests (shells) in foraminifera could be taken as an indicator that this protist taxon is unlikely to possess ectosymbionts. Here, however, we describe an association between Bolivina pacifica, a foraminiferan with a calcareous test, and a rod-shaped microbe (bacterium or archaeon) that is directly associated with the pores of the foraminiferan's test. In addition to these putative ectosymbionts, B. pacifica has previously undescribed cytoplasmic plasma membrane invaginations (PMIs). These adaptations (i.e. PMIs, ectobionts), along with the clustering of mitochondria under the pores and at the cell periphery, suggest active exchange between the host and ectobiont. The B. pacifica specimens examined were collected from sediments overlain by oxygen-depleted bottom waters (0.7 µM) of the Santa Barbara Basin (California, USA). An ultrastructural comparison between B. pacifica from the Santa Barbara Basin and a congener (Bolivina cf. B. lanceolata) collected from well-oxygenated sediments (Florida Keys) suggests that PMIs, ectobionts and peripherally distributed mitochondria are all factors that promote inhabitation of microxic environments by B. pacifica. The calcitic δ(13)C signatures of B. pacifica and of a co-occurring congener (B. argentea) that lacks ectobionts differ by > 1.5, raising the possibility that the presence of ectobionts can affect incorporation of paleoceanographic proxies.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Água do Mar
/
Simbiose
/
Bactérias
/
Foraminíferos
País/Região como assunto:
America do norte
Idioma:
En
Revista:
Environ Microbiol
Assunto da revista:
MICROBIOLOGIA
/
SAUDE AMBIENTAL
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Estados Unidos