symbiotic bacteria of oligochaetes-an interesting paper

skips

Arachnobaron
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I thought a few people here would find this paper I came across interesting. For two seconds of background, 99% of microbes are uncultureable and therefore cant be identified by standard techniques. Now people just take mass sequences of DNA and run them against a database to identify gene function and assign taxonomy.

Nature 443, 950-955 (26 October 2006) | doi:10.1038/nature05192; Received 5 May 2006; Accepted 29 August 2006; Published online 17 September 2006; Corrected 26 October 2006

Symbiosis insights through metagenomic analysis of a microbial consortium

Tanja Woyke1,2, Hanno Teeling3, Natalia N. Ivanova1, Marcel Huntemann3, Michael Richter3, Frank Oliver Gloeckner3,4, Dario Boffelli1,2, Iain J. Anderson1, Kerrie W. Barry1, Harris J. Shapiro1, Ernest Szeto1, Nikos C. Kyrpides1, Marc Mussmann3, Rudolf Amann3, Claudia Bergin3, Caroline Ruehland3, Edward M. Rubin1,2 & Nicole Dubilier3

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Abstract

Symbioses between bacteria and eukaryotes are ubiquitous, yet our understanding of the interactions driving these associations is hampered by our inability to cultivate most host-associated microbes. Here we use a metagenomic approach to describe four co-occurring symbionts from the marine oligochaete Olavius algarvensis, a worm lacking a mouth, gut and nephridia. Shotgun sequencing and metabolic pathway reconstruction revealed that the symbionts are sulphur-oxidizing and sulphate-reducing bacteria, all of which are capable of carbon fixation, thus providing the host with multiple sources of nutrition. Molecular evidence for the uptake and recycling of worm waste products by the symbionts suggests how the worm could eliminate its excretory system, an adaptation unique among annelid worms. We propose a model that describes how the versatile metabolism within this symbiotic consortium provides the host with an optimal energy supply as it shuttles between the upper oxic and lower anoxic coastal sediments that it inhabits.
 

cacoseraph

ArachnoGod
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nice stuff

i am very interested in invert pathogen and symbionts




do you have link to full paper?
 

skips

Arachnobaron
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Metagenomic analysis is pretty new and is being applied to pretty much everything microbiological. These microbial ecology studies of endosymbiont bacteria are coming out lightning quick. If you're interested, here's another.

Inherited Fungal and Bacterial Endosymbionts of a Parasitic Wasp and Its Cockroach Host
Journal Microbial Ecology
Publisher Springer New York
ISSN 0095-3628 (Print) 1432-184X (Online)
Issue Volume 57, Number 3 / April, 2009
Category Original Article
DOI 10.1007/s00248-008-9436-1
Pages 542-549
Subject Collection Biomedical and Life Sciences

Direct link to the paper is:
http://www.springerlink.com/content/v0g4566tn7205253/fulltext.html
 

cacoseraph

ArachnoGod
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ah, for pay only. eventually i will have to start scavenging for free ones again :)


i find beneficial symbionts interesting, but i am actually much more interested in the pathological varieties.

i am pretty convinced there are many slightly to very pathological endo's out there that are "infesting" the hobby... it is part of why i always take a 100% strict "no hobbyist should ever release anything back into nature" stance. it cracks me up cuz everything i have read makes me think i am right... and yet ppl who haven't read or thought about thing one see fit to argue with me as if we are on equal footing. by cracks me up i mean burns me up. i don't care what ppl do with their own bugs, really... but start putting nature as a whole (even if just a tiny microniche) and i start to get rather annoyed rather quickly
 

skips

Arachnobaron
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Yeah, that's why I didnt post the direct link. You might try joining JStor, just google it. You join as member but it's most definatley ligit and free.

I'm not sure what exactly you're refering to that would make you think that
pathogenic bacteria have entered the hobby, but its not like it's unlikely. ref:

[Photorhabdus: towards a functional genomic analysis of a symbiont and pathogen

Richard Ffrench-Constanta*, Nicholas Waterfielda, Phillip Daborna, Susan Joycea, Helen Bennetta, Candy Aua, Andrea Dowlinga, Sam Boundya, Stuart Reynoldsa, David Clarkea

Pathogenicity and symbiosis are central to bacteria–host interactions. Although several human pathogens have been subjected to functional genomic analysis, we still understand little about bacteria–invertebrate interactions despite their ecological prevalence. Advances in our knowledge of this area are often hindered by the difficulty of isolating and working with invertebrate pathogenic bacteria and their hosts. Here we review studies on pathogenicity and symbiosis in an insect pathogenic bacterium Photorhabdus and its entomopathogenic nematode vector and model insect hosts. Whilst switching between these hosts, Photorhabdus changes from a state of symbiosis with its nematode vector to one of pathogenicity towards its new insect host and both the bacteria and the nematode then cooperatively exploit the dying insect. We examine candidate genes involved in symbiosis and pathogenicity, their secretion and expression patterns in culture and in the host, and begin to dissect the extent of their genetic coregulation. We describe the presence of several large genomic islands, putatively involved in pathogenicity or symbiosis, within the otherwise Yersinia-like backbone of the Photorhabdus genome. Finally, we examine the emerging comparative genomics of the Photorhabdus group and begin to describe the interrelationship between anti-invertebrate virulence factors and those used against vertebrates.]

I've got to say though, as i'm looking around, not too many studies look like they've been done to identify invert pathogenic bacteria...I mean accept for bacillus thuringiensis with genetically modified foods. Its not hard to see that some in the hobby are pretty clueless when it comes to ecology, as separate from simple zoology. Knowing what a pedipalp is and how to keep an animal alive is just hitting the very tip of the iceberg of what one could know. It's really interesting move between boards like dendroboard and here. Here people will jump down your throat and neglect any kind of argument that would limit the hobby or their "rights". Because dendroboard is concerned with several endangered species of dart frogs, things are a lot different. People limit themselves because that's what responsible keepers do.

Also, regarding the pathogen argument, anyone that has any zoo experience knows that you keep your animals in quarantine for about 6 months before introducing them to the animals...why? Because disease is easily spread.

Long story short, you're preaching to the quire. I'd like to know what your reasons are for the below statements though.



ah, for pay only. eventually i will have to start scavenging for free ones again :)


i find beneficial symbionts interesting, but i am actually much more interested in the pathological varieties.

i am pretty convinced there are many slightly to very pathological endo's out there that are "infesting" the hobby... it is part of why i always take a 100% strict "no hobbyist should ever release anything back into nature" stance. it cracks me up cuz everything i have read makes me think i am right... and yet ppl who haven't read or thought about thing one see fit to argue with me as if we are on equal footing. by cracks me up i mean burns me up. i don't care what ppl do with their own bugs, really... but start putting nature as a whole (even if just a tiny microniche) and i start to get rather annoyed rather quickly
 
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