TEM Imaging of Cell Ultrastructure of Novel Thermophilic Bacteria in the Phyla Chloroflexi and Aquificae
EMSL Project ID
47730
Abstract
Despite rapid advances enabled by dramatic improvements in DNA sequencing technology, the majority of microbial life remains to be cultivated and studied in the laboratory. Yet, axenic cultivation remains the gold standard in microbiology, particularly for organisms only distantly related to those that have been studied in the laboratory. We have recently obtained axenic cultures of three novel bacteria from Great Boiling Spring (GBS), Nevada, a terrestrial spring which has been the focus of an intense and highly integrated research program for several years. One organism, provisionally named “Thermoflexus hugenholtzii”, is the most abundant microorganism in sediments in the source pool of GBS and is present in geothermal springs on at least four continents. A second organism, “Thermocrinis jamiesonii”, is a member of the bacterial phylum Aquificae, which is likely the most abundant bacterial group in high-temperature geothermal ecosystems worldwide. “Thermocrinis jamiesonii” is the most abundant planktonic microorganism in GBS and is physiologically distinct from its closest relatives. Finally, a third organism, “Kallotenue papyrolyticum”, represents a novel lineage within the Chloroflexi and can digest microcrystalline cellulose as a sole carbon and energy source, making it potentially useful for the biofuels industry. We have completed detailed physiological characterization of all three organisms and are in advanced stages of writing three manuscripts to be submitted to the International Journal of Systematic and Evolutionary Microbiology to propose a new class, species, and order for “Thermoflexus hugenholtzii”, “Thermocrinis jamiesonii”, and “Kallotenue papyrolyticum”, respectively. However, a basic description of cell ultrastructure is required for publications proposing new taxa and remains the final hurdle for submitting these three manuscripts. We propose collaboration with Alice Dohnalkova at EMSL to complete ultrastructural study of these three novel taxa by transmission electron microscopy with the following specific aims: (i) to describe basic cell morphology including cell size, shape, and arrangement in filaments (for “Thermoflexus hugenholtzii” and “Kallotenue papyrolyticum”), (ii) to describe basic cell surface structure (e.g. number of membranes, S-layer structure, and sleeve structure), and (iii) to describe internal cell structures and cell appendages (e.g. storage granules, pili, fimbriae, or flagella). Specific outcomes will include publication of three manuscripts, enhanced relationships between EMSL personnel and the Hedlund laboratory, and possible justification for deeper interrogation of the ultrastructure of one or more of the taxa.
Project Details
Project type
Limited Scope
Start Date
2012-12-17
End Date
2013-02-16
Status
Closed
Released Data Link
Team
Principal Investigator
Related Publications
Cole JK, BA Gieler, DL Heisler, MM Palisoc, AJ Williams, AC Dohnalkova, H Ming, TT Yu, JA Dodsworth, W-J Li, and BP Hedlund. 2013. "Kallotenue papyrolyticum gen. nov., sp. nov., a cellulolytic and filamentous thermophile that represents a novel lineage (Kallotenuales ord. nov., Kallotenuaceae fam. nov.) within the class Chloroflexia." Int J Syst Evol Microbiol 63:4675-4682. doi:10.1099/ijs.0.053348-0