Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1128/AEM.03118-16
Title (Primary) Microaerophilic Fe(II)-oxidizing Zetaproteobacteria isolated from low-Fe marine coastal sediments: Physiology and compostition of their twisted stalks
Author Laufer, K.; Nordhoff, M.; Halama, M.; Martinez, R.E.; Obst, M.; Nowak, M.; Stryhanyuk, H.; Richnow, H.H.; Kappler, A.
Source Titel Applied and Environmental Microbiology
Year 2017
Department ISOBIO
Volume 83
Issue 8
Page From e03118-16
Language englisch
UFZ wide themes ProVIS; RU4
Abstract Microaerophilic Fe(II)-oxidizers are commonly found in habitats containing elevated Fe(II) and low O2 concentrations and often produce characteristic Fe mineral structures, so-called twisted stalks or tubular sheaths. Isolates originating from freshwater habitats are all members of the Betaproteobacteria, while isolates from marine habitats belong almost exclusively to the Zetaproteobacteria. So far only few isolates of marine microaerophilic Fe(II)-oxidizers have been described, all of which are obligate microaerophilic Fe(II)-oxidizers and have been thought to be restricted to Fe-rich systems. Here we present two new isolates of marine microaerophilic Fe(II)-oxidizing Zetaproteobacteria that originate from typical coastal marine sediments containing only low Fe concentrations (2-11 mg total Fe/g sediment dry weight; 70-100 μM dissolved Fe2+in the porewater). The two novel Zetaproteobacteria share characteristic physiological properties of the Zetaproteobacteria group, even though they come from low-Fe environments: The isolates are obligate microaerophilic Fe(II)-oxidizers and like most isolated Zetaprotebacteria they produce twisted stalks. We found a low organic carbon content in the stalks (∼0.3 weight-%) with mostly polysaccharides and saturated aliphatic chains (most likely lipids). The Fe minerals in the stalks were identified as lepidocrocite and possibly ferrihydrite. Immobilization experiments with Ni2+ showed that the stalks can function as a sink for trace metals. Our findings show that obligate microaerophilic Fe(II)-oxidizers belonging to the Zetaproteobacteria group are not restricted to Fe-rich environments but can also be found in low-Fe marine environments, which increases their overall importance for the global biogeochemical Fe cycle.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=18554
Laufer, K., Nordhoff, M., Halama, M., Martinez, R.E., Obst, M., Nowak, M., Stryhanyuk, H., Richnow, H.H., Kappler, A. (2017):
Microaerophilic Fe(II)-oxidizing Zetaproteobacteria isolated from low-Fe marine coastal sediments: Physiology and compostition of their twisted stalks
Appl. Environ. Microb. 83 (8), e03118-16 10.1128/AEM.03118-16