A Microbial Biorealm page on the genus Gramella forsetii
Higher order taxa
Kingdom: Bacteria; Group: Bacteroidetes; Phylum: formerly Cytophaga-Flavobacteria-Bacteroides(CFB)
Description and significance
This specie was first found and isolated from concentrated seawater collected in the German Bight of the North Sea during a phytoplankton bloom. They represent significant part of free-living microbial assemblages in nutrient-rich microenvironments. Organisms of this group are significant in that they specialize in degradation of high molecular weight compounds in both the dissolved and particulate fraction of the marine organic matter pool. Thus, they hold a major role of Bacteroidetes in the marine carbon cycle.
'Gramella forsetii' KT0803. Size: 3.8 Mb; Chromosome: 1, Circular
Analysis of the genomes reveal a substantial suite of genes that encode hydrolytic enzymes. They are a predicted preference for polymeric carbon sources and a distinct capability for surface adhesion.
Cell structure and metabolism
This marine Bacteroidetes has a gram negative like outer structure as well as a rod shape appearance. Because they are found on macroscopic organic matter particles (marine snow), their metabolism pertains to a non-halophilic, aerobic, and mesophilic environment. Specialized genes encoding for hydrolytic enzymes reveals adaptations to degradation of polymeric organic matter.
This organism is found in seawater on organic matter particles. Their abundance and distribution pattern reveal their capability to live in diverse and nutrient-rich microenvironments. Their contributions to the environment are dedicated to the marine carbon cycle.
Related organisms that are also in the Group Bacteroidetes may include many important periodontal pathogens.
Application to Biotechnology
Despite a lack of comprehensive molecular data on this organism, we can be sure that they encode a series of genes that produce enzymes which serve in the process of degradation of organic matter.
The Max Planck Institute for Marine Microbiology is currently conducting a comparative genome analysis on strain Gramella forsetii KT0803. They isolated the organism from concentrated seawater in the North Sea. They sampled surface waters weekly, and bacteria were grown on agar plates enriched with synthetic seawater medium. Gramella forsetii was isolated from a single coloy and grown in liquid culture. By identifying its 16S rRNA phylogeny, it was then assigned to the Gramella genus. They are looking deeper into the mechanism of adaptations to degradation of polymeric organic matter as well as understanding its influence on marine microenvironments and the habitat it resides.
A close related organism named Gramella echinicola was isolated from the sea urchin Strongylocentrotus intermedius, which inhabits the Sea of Japan. This study was conducted in the Pacific Institute of Bioorganic Chemistry. This novel marine bacterium, strain KMM 6050T has similar cellular structures as well as genome lineage. The strain studied was aerobic, heterotrophic, yellow-orange-pigmented, motile by gliding, Gram-negative and oxidase-, catalase-, beta-galactosidase- and alkaline phosphatase-positive. More studies is being conducted at the moment.
The Hong Kong University of Science and Technology has also conducted studies on another related organism named Gramella portivictoriae, a novel member of the family Flavobacteriaceae. Gramella portivictoriae is a yellow-pigmented, Gram-negative, slowly gliding, rod-shaped, strictly aerobic bacterium UST040801-001T. It was isolated from marine sediment from Victoria Harbour. The gene sequence was determined using terminator method. Anaerobic growth was observed.
Bauer, M. Kube, M., Teeling, H., Richter, M., Lombardot, T., Allers, E., Wurdemann, C.A., Quast, C., Kuhl, H., Knaust, F., Woebken, D., Bischof, K., Mussmann, M., Choudhuri, J.V., Meyer, F., Reinhardt, R., Amann, R.I., and Glockner, F.O. "Whole genome analysis of the marine Bacteroidetes 'Gramella forsetii' reveals adaptations to degradation of polymeric organic matter." Environ. Microbiol. (2006) 8:2201-2213. Published online 4 October 2006.
[Sample reference] Takai, K., Sugai, A., Itoh, T., and Horikoshi, K. "Palaeococcus ferrophilus gen. nov., sp. nov., a barophilic, hyperthermophilic archaeon from a deep-sea hydrothermal vent chimney". International Journal of Systematic and Evolutionary Microbiology. 2000. Volume 50. p. 489-500.
Edited by student of Rachel Larsen and Kit Pogliano