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Microbial Metabolism

and Energetics MCB 6417 (1 credit)

Sections 7138 and 1G63

Fall 2018

Instructors

Claudio Gonzalez, Ph.D.

Contact information: email: cfgonzalez@ufl.edu, Department of Microbiology and Cell

Science, office location Genetics Institute Building Rm. GI306, phone 352-273-8088,

office hours Wednesday morning or by appointment.

Preferred method for communication with the instructor regarding the course is by e-mail (cfgonzalez@ufl.edu)

Julie A. Maupin-Furlow, PhD. twitter - @Maupin_Furlow

Contact information: email: jmaupin@ufl.edu, Department of Microbiology and Cell

Science, office location Microbiology and Cell Science Bldg 981 Museum Rd., Rm 1153

phone 352-392-4095, office hours Wednesday morning or by appointment

Preferred method for communication with the instructor regarding the course is by email (jmaupin@ufl.edu). Please resolve technical issues by contacting the UF helpdesk (http://helpdesk.ufl.edu; (352) 392-HELP (4357); helpdesk@ufl.edu · HUB 132).

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Delivery Method/Meeting time ALL ASSIGNMENTS, QUESTION /ANSWER SESSIONS AND OTHER MATERIALS

WILL BE AVAILABLE ONLINE ASYNCHRONOUSLY through Canvas. Class

discussion sessions will be held in Canvas through ‘conferences’ for off-campus

students to ask questions and interact with their instructor. The on-campus sessions will

be taped for those students who attend the class online. Students will have 700 min of

contact time associated with this 1 credit course.

Credits - 1

Course Description MCB6417. Microbial Metabolism and Energetics. Credits: 1. Principles of energy and

biosynthetic metabolisms will be examined in aerobic and anaerobic microorganisms.

Current biotechnology practices that incorporate these principles will also be discussed.

Course Objectives/Goals/Learning Outcomes To develop the concepts and skills required to understand and critically evaluate

research that addresses the physiology and biochemistry of microbes.

To apply the theories of bacterial cell physiology and metabolism to current problems, such as engineering microorganisms to produce biofuels and other products.

To utilize knowledge and skills in reviewing peer’s projects.

Course Material and Assignments

All required course materials will be available through the Canvas e-Learning site

(http://elearning.ufl.edu/). Instructions for and submission of assignments will also be

through Canvas.

Maupin-Furlow – Weeks 1-2

Group topics for the first two weeks are focused on the discovery of novel metabolic

pathways through study of microbes, examining how life has adapted to extreme energy

limitation, understanding that electron bifurcation can be added to the list of basic forms

of energy conservation (along with substrate level phosphorylation and membrane

bioenergetics), and theorizing on the bioenergetics of life’s origins.

Assignments Weeks 1-2 (see below for details)

100 points Group presentation (oral report)

75 points Scientific summaries

25 points Scientific evaluations

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Group presentation – oral report (100 points): The class will be divided into groups

of ~3-4 students per group. Each group will prepare and present an oral report on a

topic related to microbial metabolism and energetics that will be assigned by the

instructor (see Appendix A at the end of this syllabus for details). Each student within

the group is responsible for coordinating and presenting with fellow group members the

oral report on their assigned topic. Please note that each student within the group

will be graded independently of their group members (e.g., students within the

same group may not earn the same grade). Students should initial each slide that

they prepared and present to allow for independent evaluation of their work by the

instructor. Each student should also introduce himself/herself prior to speaking.

Overall, the group is expected to prepare an oral report that is a total of 15-20 min

(estimate ~1 min per slide). Students are expected to perform a literature review

related to the topic of discussion and synthesize the material into a comprehensive

presentation. A reference list is provided for each topic to assist group members in

getting started on the literature review and prepare the group presentation. The

reference list is not meant to be exclusive. Students are encouraged to find additional

literature related to the topic of discussion. Students are expected to critically evaluate

the literature and gain a deep understanding of the metabolic process under discussion

prior to preparing the oral presentation. Students should clearly explain the topic in a

manner that is scientifically accurate using their own words – do not plagiarize. To add

excitement to the oral report – please take the time to discover what aspects of the topic

may be on the cutting edge of new knowledge in the field.

Scientific summaries (75 points): Students are expected to write an independent

summary of the material presented by their peer groups (not their own oral report).

This work should be performed by each individual student – it is not a group effort. The

summaries should be 1/2 page (typed, double spaced, 1-inch margins) for each

group. The summaries should focus on the science presented by the groups. A final

sentence at the end of the summary that speculates on future research efforts and/or

discoveries that are related to the group topic under discussion is encouraged.

Scientific evaluations and rankings (25 points): Each student should provide an independent scientific review for each project presented by their peers (not their own oral report) – this is not a group effort. The evaluation should include careful justification for the criticisms and positive comments, to provide helpful feedback. The reviews should include the strengths and weaknesses of the project (3-4 sentences per group) as well as evaluation scores (1 highest – 10 lowest) for the overall presentation and each of the following criteria (similarly to an NIH review panel):

• Scientific Accuracy • Approach • Innovation • Impact

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Plagiarism: Please note that plagiarism is against the UF honor code (for details see

https://www.dso.ufl.edu/sccr/process/student-conduct-honor-code/) (online modules are

also available to assist you with making ethical decisions regarding plagiarism and other

codes of conduct at https://www.dso.ufl.edu/sccr/seminars-modules/).

“(a) Plagiarism. A student shall not represent as the student's own work all or any

portion of the work of another. Plagiarism includes but is not limited to:

1. Quoting oral or written materials including but not limited to those found on the

internet, whether published or unpublished, without proper attribution."

You must use your own words to communicate oral and written materials presented in

the oral reports, scientific evaluations, and summaries of this course.

Use the following criteria as a guideline for the oral report(s).

Organization: Did the group state the presentation topic? Was there a main point? Was the presentation clearly organized?

Scientific Presentation: Did the group back up their analysis with scientific facts, statistics, statements from authorities, figures from relevant papers, etc.? Did the group use scientific terms and define these terms for the class?

Analysis and Synthesis: Did the group synthesize the information in the literature or just give a "book report" on what was found?

Use of Visual Aids: Did the visual aids add to the quality of the presentation? Were they visible from the back of the room?

Sources: Did the group give proper credit to people whose ideas they borrowed (citations)? Were figures/diagrams properly attributed to specific sources?

Overall Quality: Was the group prepared? Did the group present adequate information? Could the students hear what the speakers were saying? Was the presentation interesting and intriguing? Did the group have a good command of the material presented?

Guidelines for recording the group presentations

1. Develop an outline for the oral presentation as soon as possible. Note that the

outline of the group presentation should not be paper 1, paper 2, paper 3, etc.

but instead should be a synthesis of the literature. Thus, each student within

the group should read the papers of the presentation and assist in synthesizing

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the material into an outline that will generate a presentation that is

comprehensive.

2. Use the outline to evenly divide the labor among each student in the group.

3. Remember that each slide should be ~ 1 min for a total of 15-20 min.

4. Record the slide presentation including slides and an audio recording designed

to teach/guide the viewer. Identify yourself during the recording and include your

initial on each slide that you generated (if others helped generate the slide –

please be sure to acknowledge their assistance).

5. Record the slide show using a tool such as the ‘record slide show’ option of

Powerpoint version 2016 or higher.

6. The recordings can be performed separately by each student in the group and

then merged into a single Powerpoint (.ppt) file.

7. Once complete, the presentations should be submitted through Canvas

electronically.

Gonzalez (Weeks 3-4)

During weeks 3 and 4, students

Presentations (100): The group presentations will be done using power point or similar

software. The groups will be integrated by a maximum of 4 members. A presentation

podcast should be posted on line following the schedule provided (See First class

Power Point). Grades will be assigned as follow

1) Research ability and critical thinking (50 pts): We will evaluate the

ability to select the relevant information. An important component of

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critical thinking is the ability to generate on line discussion and deliver

relevant information to the rest of the groups.

2) Quality and clarity (50 Points). We will evaluate the graphic material

selected, and originality to display information graphically.

Final report (100 pts): Individual participation will be evaluated according to the ability of

each student to summarize and connect all the information provided in a final report.

This final paper (4 to 5 pages long) should clearly and rationally establish solid links

between all the information discussed during the course.

Weekly Course Schedule

Maupin-Furlow – (JMF weeks 1-2)

Week 1 R 08/23 Introduction to the course – students assigned to groups for presentations T 08/28 Group presentations - preparation Week 2 R 08/30 Group presentations - preparation T 09/04 Group presentations – preparation W 09/05 Deadline for group presentations (JMF weeks 1-2)- submit via Canvas Gonzalez (See Canvas for Groups and PPT Schedule) Week 3 R 09/06 Introduction – Surprising Metabolic Intersection to Maximize Metabolic Efficiency – Carbon Overflows. T 09/11 Group Presentations (Students should work in presentations) Week 4 R 09/13 Group Presentations (Students should work in presentations) T 09/18 Presentations should be posted in Canvas: Consequences of Metabolic

Overflow - Engineering pathways – Metabolic regulation with multiple connections.

Week 5 Sun 09/23 Dealine for scientific summaries and evaluations (JMF weeks 1-2)

of group presentations – submit via Canvas Week 6 Sat 9/29 Gonzalez Final Report: September 29; 2018. GENERAL REFERENCE TEXTBOOKS:

White, D. 2006. The Physiology and Biochemistry of Prokaryotes. Third Edition. Oxford

University Press, New York, NY. ISBN 0-19-530168-4.

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Garrett, R. A. and Klenk, H.-P. 2007. Archaea. Blackwell Publishing, Malden, MA. ISBN-

13: 978-1-4051-4404-9 and ISBN-10: 1-4051-4404-1.

[Exam Dates/Calendar/Critical dates and deadlines] Deadlines

09/05 Group oral presentation (100 pts, JMF section)

09/11 Presentations (Gonzalez section, 50 pts)

09/23 Scientific summaries of peer groups (75 pts, JMF section)

09/23 Scientific evaluations of peer groups (25 pts, JMF section)

09/29 Final Report (Gonzalez section, 100 pts)

Evaluation of Learning/Grades

MCB 6417 learning will be evaluated based on the following criteria:

100 points Group oral presentation (JMF section) 75 points Scientific summaries (JMF section) 25 points Scientific evaluations (JMF section) 50 points Presentations quality. (CFG section) 50 points Research ability and critical thinking (CFG section) 100 points Final Report (CFG section) 400 points total

[Materials and Supplies Fees] There are no additional fees for this course.

Grading Policy Final grades will be based on the following performance standard:

95 - 100 % = A

90 - 94 % = A-

87 - 89 % = B+

84 - 86 % = B

80 - 83 % = B-

77 - 79 % = C+

74 - 76 % = C

70 - 73 % = C-

60 - 69 % = D

Less than 60 % = E

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More information on grades and grading policies is here: https://catalog.ufl.edu/ugrad/current/regulations/info/grades.aspx

Class Attendance and Make-Up Policy Excused absences are consistent with university policies in the undergraduate catalog (https://catalog.ufl.edu/ugrad/current/regulations/info/attendance.aspx) and require appropriate documentation. Excused absences from exams and/or assignments (e.g., illness, serious family emergency, military obligations, religious holidays) must be communicated by formal signed documentation to the instructor prior to the missed exam or assignment. Appropriate documentation MUST be provided for the absence caused by serious illness, accident, jury duty or death in the immediate family. You MUST contact the instructor IN ADVANCE of the missed exam or assignment. An alternative time for the exam and/or assignment will be arranged by the instructor.

Students Requiring Accommodations Students with disabilities requesting accommodations should first register with the Disability Resource Center (352-392-8565, www.dso.ufl.edu/drc/) by providing appropriate documentation. Once registered, students will receive an accommodation letter which must be presented to the instructor when requesting accommodation. Students with disabilities should follow this procedure as early as possible in the semester.

Campus Resources Resources are available on campus for students having personal problems or lacking clear career and academic goals, which interfere with their academic performance. These resources include:

Health and Wellness U Matter, We Care: If you or a friend is in distress, please contact

umatter@ufl.edu or 352 392-1575 so that a team member can reach out to the student.

Counseling and Wellness Center: http://www.counseling.ufl.edu/cwc/Default.aspx, 392-1575;

Sexual Assault Recovery Services (SARS) at the Student Health Care Center, 392-1161.

For emergencies call: University Police Department, 392-1111 (or 9-1-1 for emergencies). http://www.police.ufl.edu/

Academic Resources E-learning technical support, 352-392-4357 (select option 2) or e-mail to

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Learning-support@ufl.edu. https://lss.at.ufl.edu/help.shtml.

Career Resource Center, Reitz Union, 392-1601. Career assistance and counseling. http://www.crc.ufl.edu/

Library Support, http://cms.uflib.ufl.edu/ask. Various ways to receive assistance with respect to using the libraries or finding resources.

Teaching Center, Broward Hall, 392-2010 or 392-6420. General study skills and tutoring. http://teachingcenter.ufl.edu/

Writing Studio, 302 Tigert Hall, 846-1138. Help brainstorming, formatting, and writing papers. http://writing.ufl.edu/writing-studio/

Course Evaluation Students are expected to provide feedback on the quality of instruction in this course by completing online evaluations at https://evaluations.ufl.edu. Evaluations are typically open during the last two or three weeks of the semester, but students will be given specific times when they are open. Summary results of these assessments are available to students at https://evaluations.ufl.edu/results/.

Class demeanor Students are expected to arrive to class on time and behave in a manner that is respectful to the instructor and to fellow students. Please avoid the use of cell phones and restrict eating to outside of the classroom. Opinions held by other students should be respected in discussion, and conversations that do not contribute to the discussion should be held at minimum, if at all.

Netiquette guide for online courses It is important to recognize that the online classroom is in fact a classroom, and certain behaviors are expected when you communicate with both your peers and your instructors. These guidelines for online behavior and interaction are known as netiquette. http://teach.ufl.edu/wp-content/uploads/2012/08/NetiquetteGuideforOnlineCourses.pdf

University Honesty Policy UF students are bound by The Honor Pledge which states, “We, the members of the University of Florida community, pledge to hold ourselves and our peers to the highest standards of honor and integrity by abiding by the Honor Code. On all work submitted for credit by students at the University of Florida, the following pledge is either required or implied: “On my honor, I have neither given nor received unauthorized aid in doing this assignment.” The Honor Code (https://www.dso.ufl.edu/sccr/process/student-conduct-honor-code/) specifies a number of behaviors that are in violation of this code and the possible sanctions. Furthermore, you are obligated to report any condition that facilitates academic misconduct to appropriate personnel. If you have any questions or concerns, please consult with the instructor or TAs in this class.

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Software Use

All faculty, staff and students of the university are required and expected to obey the

laws and legal agreements governing software use. Failure to do so can lead to

monetary damages and/or criminal penalties for the individual violator. Because such

violations are also against university policies and rules, disciplinary action will be taken

as appropriate.

Microsoft Office 365 Software is free for UF students

http://www.it.ufl.edu/gatorcloud/free-office-365-downloads/

Other free software is available at:

http://www.software.ufl.edu/

To check for availability of the media and technical requirements, contact the UF

Computing Help Desk at (352)392-HELP(4357).

University of Florida Complaints Policy and Student

Complaint Process Most problems, questions and concerns about the course will be resolved by professionally communicating with the instructor or the TAs. The University of Florida believes strongly in the ability of students to express concerns regarding their experiences at the University. The University encourages its students who wish to file a written complaint to submit that complaint directly to the department that manages that policy. If a problem really cannot be resolved by communicating with the instructor or the TAs you can contact

Residential Course: https://www.dso.ufl.edu/documents/UF_Complaints_policy.pdf.

Online Course: http://www.distance.ufl.edu/student-complaint-process.

University of Florida U Matter

Your well-being is important to the University of Florida. The U Matter, We Care initiative is committed to creating a culture of care on our campus by encouraging members of our community to look out for one another and to reach out for help if a member of our community is in need. If you or a friend is in distress, please contact umatter@ufl.edu so that the U Matter, We Care Team can reach out to the student in distress. A nighttime and weekend crisis counselor is available by phone at 352-392-1575. The U Matter, We Care Team can help connect students to the many other helping resources available including, but not limited to, Victim Advocates, Housing staff, and the Counseling and Wellness Center. Please remember that asking for help is a sign of strength. In case of emergency, call 9-1-1.

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Appendix A (JMF section – weeks 1-2)

The first two weeks of MCB6417 Microbial Metabolism and Energetics will be as follows

(please see earlier sections of the syllabus for additional details).

1. The class will be divided into groups of ~3-4 students. 2. The topic of the group presentation will be assigned by the instructor to avoid

delay and assure that material related to metabolism will be uniformly covered. 3. All group presentations should include visual aids and audio to guide the viewer

in the knowledge that each group is conveying. 4. Each group should select a leader who will upload the oral report as a

powerpoint (.ppt) file (that includes audio links within the presentation) through Canvas http://elearning.ufl.edu/

5. The deadline for uploading ALL group presentations is Sept. 5, 2018. 6. Each group presentation should be 15-20 min in length. 7. Each student within the group is responsible for coordinating and presenting with

fellow group members the oral presentation on their assigned topic.

8. Students should use their own words and should initial each slide that they are presenting to allow for evaluation of their work by the instructor. Students should also introduce themselves prior to speaking.

9. Each student should write a “summary” and a brief “evaluation” for each presentation (excluding their own) by no later than Sept. 23, 2018. This portion of the course is not a group project – the student should write the summaries and evaluations on his/her own.

10. Each “summary” should be 1/2-page double spaced and should briefly summarize the scientific information covered in the presentation (e.g., 6 pages total for 12 presentations). The summary should not evaluate the quality of the presentation, but instead should focus on the science.

11. Each student should also write a 3-4 sentence “evaluation” for each presentation (excluding your own). The evaluation is your carefully formulated opinion vs. the “summary” which is a summary of the science. Please rate the presentations for a) Scientific Accuracy, b) Approach, c) Innovation, and d) Impact (scale 1-10, 1 highest and 10 lowest – similarly to NIH). Be sure to provide an overall score. Your criticism and praises should be carefully justified with appropriate rationale based on the presentation.

12. If you have any questions – PLEASE feel free to ASK. I am available for meeting one-on-one or with groups to answer questions regarding the literature, class policy, etc.

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Group Presentations: Group Numbers and Topics (JAMF section, weeks 1-2).

Below please find the group topics with some references to get your started. The

reference list is not meant to be exclusive. Students are encouraged to find additional

literature related to the topic of discussion. Do not assign paper 1 to student 1 etc., as

the presentation will be unorganized and will have a lot of redundant overlap. Students

are expected to critically evaluate the literature chosen for the presentation and to gain

a deep understanding of the metabolic process under discussion prior to preparing the

oral presentation. Please be sure to discuss the group topic as it relates to the

basic mechanisms of microbial metabolism and bioenergetics. The basic

mechanisms of systems of higher organisms (e.g., plants and humans) can be used for

comparison to the microbial systems under discussion; however, the microbial systems

should be the central focus of the report. Biotechnology applications and

positive/negative impacts on humans are helpful to highlight at the end of the oral

report. The references cited in the subheadings are listed by author, title, journal,

volume and page number at the end of the topics section (remember – this list is not

meant to be comprehensive).

1. Flavin-based electron bifurcation – a newly discovered form of energy conservation

a. Overview (1-6) b. Recent structural insight (7) c. The role of mass spectrometry in structural studies associated with flavin-

based electron bifurcation (8) d. Discovery of new enzymes in the pathway (9) e. Biotechnology applications (10,11)

2. Methanogenesis and the Wood-Ljungdahl pathway – ancient metabolisms

with modern biotechnology applications a. Overview of methanogenesis (3,12,13) b. Acetotrophic methanogenesis (14) c. Beyond known methanogens (15,16) d. Methanogenic CO2 reducing-and-fixing enzymes (17) e. Biotechnology applications (18-21) (please remember that group 1 is presenting flavin-based electron bifurcation and group 3 is presenting reverse methanogenesis)

3. Anaerobic oxidation of methane (AOM) – the consumption of methane at the

edge of life a. AOM overview (22-24) a. AOM in ANME archaea (25) b. Thermophilic AOM (26) c. Anaerobic oxidation of butane and its relationship to AOM (27) d. Electron transfer between methanotrophic archaea and bacteria (28) e. Communal metabolism of methane (29)

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4. Complete ammonia oxidizers (comammox) - pivotal players in nitrification

(30-37)

5. Ammonia oxidizing archaea (AOA) – a resource for discovery of new central metabolic pathways

a. Ammonia oxidizing archaea overview (38,39) b. Integrated structural biology and molecular ecology (40) c. Diversity, physiology, and niche differentiation (41) d. Genomics and proteomics of AOA (42) e. Pathways and key intermediates required for obligate aerobic ammonia-

dependent chemolithotrophy in bacteria and archaea (43)

6. Selenocysteine and pyrrolysine the 21st and 22nd amino acids of protein biosynthesis (please focus on microbes)

a. Selenocysteine (44,45) b. Pyrrolysine (46-49)

7. Iron-sulfur (Fe-S) cluster biogenesis and its relationship to metabolism

(please focus on microbes) (50-52)

8. Bioenergetics at the origins of life (can discuss controversy – your choice) a. Bioenergetics and life’s origins (53-55) b. Iron catalysis at the origin of life (56) c. Remnants of an ancient metabolism without phosphate (57,58) d. Root of the archaeal tree – reduce CO2 to acetate via the Wood-Ljungdahl

pathway (59)

9. Microbial life under extreme energy limitation (be sure to clarify energy starvation vs. substrate of low energy yield)

(60-62)

10. Microbial syntrophy and interspecies electron transfer a. Microbial syntrophy (63) b. Recent findings in syntrophic consortia (64) c. Interspecies electron transfer (28,65-67) d. Microbial electroactivity (68) e. Electrofermentation (69)

11. Microbial degradation of plastics (70-72)

12. Metabolism of carbon monoxide

a. CO as fuel for anaerobes and aerobes (73) b. Anaerobic CO fermentation (74) c. Role of CO in thermophilic microbial consortia (75) d. Molecular analysis of H2 and CO metabolism of a methanogen (76)

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13. Anaerobic metabolisms of microbes from hypersaline habitats – the Dead

Sea is not dead! a. Anaerobic lithoheterotrophic haloarchaea (77) b. Methyl-reducing haloarchaea (78) c. Obligate anaerobic sulfur-respiring haloarchaeon (79,80) and its complete

genome sequence (81) d. Ecology and application of anaerobic haloalkaliphiles (82)

14. Metabolism of seafloor and subseafloor microbial communities (83-85)

15. Iron-reducing and sulfate-dependent ammonium-oxidizing microorganisms that await discovery. (32)

References (weeks 1-2):

1. Peters, J. W., Miller, A. F., Jones, A. K., King, P. W., and Adams, M. W. (2016) Electron bifurcation. Curr Opin Chem Biol 31, 146-152

2. Baymann, F., Schoepp-Cothenet, B., Duval, S., Guiral, M., Brugna, M., Baffert, C., Russell, M. J., and Nitschke, W. (2018) On the natural history of flavin-based electron bifurcation. Front Microbiol 9, 1357

3. Yan, Z., and Ferry, J. G. (2018) Electron bifurcation and confurcation in methanogenesis and reverse methanogenesis. Front Microbiol 9, 1322

4. Muller, V., Chowdhury, N. P., and Basen, M. (2018) Electron bifurcation: a long-hidden energy-coupling mechanism. Annu Rev Microbiol

5. Buckel, W., and Thauer, R. K. (2018) Flavin-based electron bifurcation, a new mechanism of biological energy coupling. Chem Rev 118, 3862-3886

6. Peters, J. W., Beratan, D. N., Bothner, B., Dyer, R. B., Harwood, C. S., Heiden, Z. M., Hille, R., Jones, A. K., King, P. W., Lu, Y., Lubner, C. E., Minteer, S. D., Mulder, D. W., Raugei, S., Schut, G. J., Seefeldt, L. C., Tokmina-Lukaszewska, M., Zadvornyy, O. A., Zhang, P., and Adams, M. W. (2018) A new era for electron bifurcation. Curr Opin Chem Biol 47, 32-38

7. Lubner, C. E., Jennings, D. P., Mulder, D. W., Schut, G. J., Zadvornyy, O. A., Hoben, J. P., Tokmina-Lukaszewska, M., Berry, L., Nguyen, D. M., Lipscomb, G. L., Bothner, B., Jones, A. K., Miller, A. F., King, P. W., Adams, M. W. W., and Peters, J. W. (2017) Mechanistic insights into energy conservation by flavin-based electron bifurcation. Nat Chem Biol 13, 655-659

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8. Tokmina-Lukaszewska, M., Patterson, A., Berry, L., Scott, L., Balasubramanian, N., and Bothner, B. (2018) The role of mass spectrometry in structural studies of flavin-based electron bifurcating enzymes. Front Microbiol 9, 1397

9. Yan, Z., Wang, M., and Ferry, J. G. (2017) A ferredoxin- and F420H2-dependent, electron-bifurcating, heterodisulfide reductase with homologs in the domains Bacteria and Archaea. MBio 8

10. Ledbetter, R. N., Garcia Costas, A. M., Lubner, C. E., Mulder, D. W., Tokmina-Lukaszewska, M., Artz, J. H., Patterson, A., Magnuson, T. S., Jay, Z. J., Duan, H. D., Miller, J., Plunkett, M. H., Hoben, J. P., Barney, B. M., Carlson, R. P., Miller, A. F., Bothner, B., King, P. W., Peters, J. W., and Seefeldt, L. C. (2017) The electron bifurcating FixABCX protein complex from Azotobacter vinelandii: generation of low-potential reducing equivalents for nitrogenase catalysis. Biochemistry 56, 4177-4190

11. Mock, J., Zheng, Y., Mueller, A. P., Ly, S., Tran, L., Segovia, S., Nagaraju, S., Kopke, M., Durre, P., and Thauer, R. K. (2015) Energy conservation associated with ethanol formation from H2 and CO2 in Clostridium autoethanogenum involving electron bifurcation. J Bacteriol 197, 2965-2980

12. Borrel, G., Adam, P. S., and Gribaldo, S. (2016) Methanogenesis and the Wood-Ljungdahl pathway: An ancient, versatile, and fragile association. Genome Biol Evol 8, 1706-1711

13. Costa, K. C., and Leigh, J. A. (2014) Metabolic versatility in methanogens. Curr Opin Biotechnol 29C, 70-75

14. Ferry, J. G. (2015) Acetate metabolism in anaerobes from the domain Archaea. Life (Basel) 5, 1454-1471

15. Lloyd, K. (2015) MICROBIOLOGY. Beyond known methanogens. Science 350, 384

16. Evans, P. N., Parks, D. H., Chadwick, G. L., Robbins, S. J., Orphan, V. J., Golding, S. D., and Tyson, G. W. (2015) Methane metabolism in the archaeal phylum Bathyarchaeota revealed by genome-centric metagenomics. Science 350, 434-438

17. Wagner, T., Ermler, U., and Shima, S. (2016) The methanogenic CO2 reducing-and-fixing enzyme is bifunctional and contains 46 [4Fe-4S] clusters. Science 354, 114-117

18. Blasco-Gomez, R., Batlle-Vilanova, P., Villano, M., Balaguer, M. D., Colprim, J., and Puig, S. (2017) On the edge of research and technological application: A critical review of electromethanogenesis. Int J Mol Sci 18

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19. Mayumi, D., Mochimaru, H., Tamaki, H., Yamamoto, K., Yoshioka, H., Suzuki, Y., Kamagata, Y., and Sakata, S. (2016) Methane production from coal by a single methanogen. Science 354, 222-225

20. Holmes, D. E., and Smith, J. A. (2016) Biologically produced methane as a renewable energy source. Adv Appl Microbiol 97, 1-61

21. Enzmann, F., Mayer, F., Rother, M., and Holtmann, D. (2018) Methanogens: biochemical background and biotechnological applications. AMB Express 8, 1

22. Cui, M., Ma, A., Qi, H., Zhuang, X., and Zhuang, G. (2015) Anaerobic oxidation of methane: an "active" microbial process. Microbiologyopen 4, 1-11

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