NAI Director's Seminar Series presents Moh El-Naggar

Event Details

NAI Director's Seminar Series presents Moh El-Naggar

Time: October 27, 2014 from 1pm to 2pm
Location: Adobe Connect
Website or Map: http://astrobiology.nasa.gov/…
Event Type: online, seminar
Organized By: Mike Toillion
Latest Activity: Oct 25, 2014

Export to Outlook or iCal (.ics)

Event Description

Hotwired Life: Microbial Energy Acquisition by Electron Transfer Across the Biotic-Abiotic Interface

Presenter: Moh El-Naggar, University of Southern California
When: October 27, 2014 1PM PDT

Reduction-oxidation (redox) reactions and electron transport are essential to life’s energy conversion pathways. But what if there was also a direct link allowing electron exchange between the living and non-living worlds? We now know that some anaerobic bacteria gain energy through extracellular electron transport to natural minerals or synthetic electrodes that serve as electron acceptors for respiration outside the cells. In addition to the fundamental implications for physiology and astrobiology, where interfacial electron transport may form the basis of an extraterrestrial metabolism on iron-rich planets, a physics-based understanding may enable the transmission and control of signals at hybrid living/synthetic interfaces.

But how can a bacterium transport electrons to an external surface? In this talk we will describe how bacteria organize redox sites on outer cell membranes, and along quasi-one-dimensional filaments known as bacterial nanowires, to facilitate long-range charge transport. The approaches taken include microfluidic fluorescence assays, gene expression profiling, single-cell electrochemical measurements, scanning tunneling microscopy of redox molecules, and nanofabrication-enabled measurements of transport along individual nanowires produced by the iron reducing bacterium Shewanella oneidensis MR-1. Based on these measurements, we propose that extracellular respiration is facilitated by an incoherent multistep charge hopping mechanism along redox chains. Finally, we will describe in vivo measurements demonstrating that the S. oneidensis MR-1 nanowires are lipid-based extensions of the outer membrane and periplasm that include the multiheme cytochromes responsible for extracellular electron transport. Redox-functionalized membrane and vesicular extensions may represent a general microbial strategy for electron transport and energy distribution.

http://connect.arc.nasa.gov/nai_directors_seminar

Comment Wall

Comment

RSVP for NAI Director's Seminar Series presents Moh El-Naggar to add comments!

Join SAGANet

Comment by Mike Toillion on October 25, 2014 at 7:31am

Yes, you can find all of our archived seminars on the NAI Seminars & Workshops page: http://astrobiology.nasa.gov/seminars/

Comment by Ivan Lima on October 24, 2014 at 3:55pm

Sounds really cool indeed. I'm not sure if I can attend yet. Will the video be recorded and posted somewhere afterwards?


Expert
Comment by Sara Imari Walker on October 24, 2014 at 2:49pm

This sounds really cool! Can't wait for the talk!

Attending (5)

Might attend (1)

Photos

  • Add Photos
  • View All

Blog Posts

¿Are the Venusian sulphuric acid clouds the by product of long dead anoxogenic photosynthetic organisms?

Posted by Andrew Planet on May 4, 2020 at 2:51pm 2 Comments

I just read the piece at the link below entitled "Study: Life might survive, and thrive, in a hydrogen world."

I'd been thinking on similar lines recently, on different atmospheres with early life, but I was considering anoxogenic bacteria whose byproduct is sulfur instead of molecular oxygen. ¿Had life evolved on Venus could its sulfuric clouds be the signature byproduct of such life with no branches ever evolving to produce the equivalent of Earth's Great…

Continue

100 years tomorrow 26th April 2020 since we looked beyond the Milky Way Galaxy

Posted by Andrew Planet on April 25, 2020 at 11:10am 0 Comments

Exactly 100 years ago tomorrow, the subject on whether this Universe is larger than the Milky Way Galaxy was brought up publicly at an event sponsored by the National Academy of Sciences, known as The Great Debate. Until then the Milky Way was thought to be this Universe.  Conference at the NAS http://www.nasonline.org/about-nas/events/annual-meeting/nas157/

See this…

Continue

The 5th Mexican School of Astrobiology

Posted by Tardigrelda on June 24, 2019 at 1:00pm 0 Comments

I am really glad to invite everyone to the next Mexican School of Astrobiology (aka EMA) which is this August.

¡Anímate a participar en la 5ta Escuela Mexicana de…

Continue

A consortium of representatives of European Research Organisations has taken the initiative to create a virtual institute named the “European Astrobiology Institute” (EAI) with the ambition of enabli…

Posted by Wolf D. Geppert on February 24, 2019 at 1:33am 0 Comments

A consortium of representatives of European Research Organisations has taken the initiative to create a virtual institute named the “European Astrobiology Institute” (EAI) with the ambition of enabling Europe to emerge as a key player in Astrobiology and to…

Continue

Videos

  • Add Videos
  • View All

Forum

Ask your questions here!

Started by Gina Riggio in SAGANet Discussions. Last reply by Mert Kabalcı 11 hours ago. 121 Replies

If you are trying to ask a question live during Ask an Astrobiologist, please do so in the main chatroom at the bottom of the screen! You can also ask on twitter…Continue

Have we been looking in the wrong time-frame? Requesting feedback on a recent paper.

Started by Christopher J Reiss in The Cutting-Edge of Astrobiology Apr 3. 0 Replies

Let me first say Hi to everyone as a new member here!   I hope you are all safe, sound, and not too stir-crazy during this Pandemic.I recently stumbled upon a notion for SETI which seems so simple I…Continue

Interactive Online Astrobiology for 10-12 yr olds

Started by Julia Brodsky in Education and Public Outreach Mar 9. 0 Replies

If your 10-12 yr old child is interested in space science, I would like to invite them to our courses. I am a former science teacher,  mom of three, and a former NASA astronaut instructor. I also…Continue

Tags: school, education, middle, astrobiology, STEM

zahra cell

Started by adam nurjaman in Education and Public Outreach Mar 7. 0 Replies

Hallo apa kabar ? semoga selalu baik2 saja zahra cell adalah blog yang…Continue

Tags: cell, zahra

© 2020   Blue Marble Space, a non-profit organization committed to science and science outreach.   Powered by

Badges  |  Report an Issue  |  Terms of Service