TY - JOUR
T1 - Development of a genetic system for Marinobacter adhaerens HP15 involved in marine aggregate formation by interacting with diatom cells
AU - Sonnenschein, Eva
AU - Gärdes, Astrid
AU - Seebah, Shalin
AU - Torres-Monroy, Ingrid
AU - Grossart, Hans-Peter
AU - Ullrich, Matthias S.
PY - 2011
Y1 - 2011
N2 - Diatom aggregation is substantial for organic carbon flux from the photic zone to deeper waters. Many heterotrophic bacteria ubiquitously found in diverse marine environments interact with marine algae and thus impact organic matter and energy cycling in the ocean. In particular, Marinobacter adhaerens HP15 induces aggregate formation while interacting with the diatom, Thalassiosira weissflogii. To study this effect at the molecular level, a genetic tool system was developed for strain HP15. The antibiotic susceptibility spectrum of this organism was determined and electroporation and conjugation protocols were established. Among various plasmids of different incompatibility groups, only two were shown to replicate in M. adhaerens. 1.4×10−3 transconjugants per recipient were obtained for a broad-host-range vector. Electroporation efficiency corresponded to 1.1×105CFU per μg of DNA. Transposon and gene-specific mutageneses were conducted for flagellum biosynthetic genes. Mutant phenotypes were confirmed by swimming assay and microscopy. Successful expression of two reporter genes in strain HP15 revealed useful tools for gene expression analyses, which will allow studying diverse bacteria–algae interactions at the molecular level and hence to gain a mechanistic understanding of micro-scale processes underlying ocean basin-scale processes. This study is the first report for the genetic manipulation of a Marinobacter species which specifically interacts with marine diatoms and serves as model to additionally analyze various previously reported Marinobacter–algae interactions in depth.
AB - Diatom aggregation is substantial for organic carbon flux from the photic zone to deeper waters. Many heterotrophic bacteria ubiquitously found in diverse marine environments interact with marine algae and thus impact organic matter and energy cycling in the ocean. In particular, Marinobacter adhaerens HP15 induces aggregate formation while interacting with the diatom, Thalassiosira weissflogii. To study this effect at the molecular level, a genetic tool system was developed for strain HP15. The antibiotic susceptibility spectrum of this organism was determined and electroporation and conjugation protocols were established. Among various plasmids of different incompatibility groups, only two were shown to replicate in M. adhaerens. 1.4×10−3 transconjugants per recipient were obtained for a broad-host-range vector. Electroporation efficiency corresponded to 1.1×105CFU per μg of DNA. Transposon and gene-specific mutageneses were conducted for flagellum biosynthetic genes. Mutant phenotypes were confirmed by swimming assay and microscopy. Successful expression of two reporter genes in strain HP15 revealed useful tools for gene expression analyses, which will allow studying diverse bacteria–algae interactions at the molecular level and hence to gain a mechanistic understanding of micro-scale processes underlying ocean basin-scale processes. This study is the first report for the genetic manipulation of a Marinobacter species which specifically interacts with marine diatoms and serves as model to additionally analyze various previously reported Marinobacter–algae interactions in depth.
KW - Marinobacter
KW - Marine aggregates
KW - Genetic toolbox
KW - Mutagenesis
KW - Bacterial motility
U2 - 10.1016/j.mimet.2011.08.008
DO - 10.1016/j.mimet.2011.08.008
M3 - Journal article
C2 - 21880271
VL - 87
SP - 176
EP - 183
JO - Journal of Microbiological Methods
JF - Journal of Microbiological Methods
SN - 0167-7012
IS - 2
ER -