Dr Marcela Hernández García

Supervisor Details

Contact Details

School of Biosciences, University of Birmingham

Scientific Background

Research Interests

My research focuses on understanding the role of microorganisms in the cycling and degradation of atmospheric trace gases, particularly carbon monoxide, methane and hydrogen, across diverse and extreme environments.

Supervision Style

In three words or phrases: Supportive, goal-driven, organised

Provision of Training

I provide PhD students with interdisciplinary training combining experimental microbiology, molecular biology, microbial ecology, bioinformatics and stable-isotope approaches.

Progression Monitoring and Management

I like to be kept up to date, and will expect to see evidence of method development/data generation results on a daily/weekly basis.

Communication

I am known to email my team/PhD students at all hours of the day and night, however I will not expect you to do the same. I am happy to discuss any issues that are impacting your ability to fulfil your potential or my/our expectations.

Meetings

PhD Students can expect scheduled meetings with me at least once per week. These meetings will be a mixture of face-to-face and via video chat or telephone. I have an open door policy, but my pattern of being contactable for an instant response is not predictable.

Work Patterns

Certain tasks in my lab need to occur at set times, and students need to be able to commit to a rota/timetable shared with other members of the team.

Notice Period for Feedback

I need at least 1 week's notice to provide feedback on written work of up to 5,000 words.

MIBTP Project Details

Primary supervisor for:

Investigating genetic markers and mechanisms of CO dehydrogenase regulation in response to atmospheric mercury

See the PhD Opportunities section to see if this project is currently open for applications via MIBTP.

Please Note: The main page lists projects via BBSRC Research Theme(s) quoted and then relevant Topic(s).

Investigating genetic markers and mechanisms of CO dehydrogenase regulation in response to atmospheric mercury

Secondary Supervisor(s): Professor Yin Chen

University of Registration: University of Birmingham

BBSRC Research Themes:

Understanding the Rules of Life (Microbiology, Soil Science)

Project Outline

Volcanic emissions are a natural source of mercury (Hg) to the atmosphere and geologists have shown that volcanoes, like Mt. Etna (Italy), is a major natural source of Hg to the atmosphere. This has clear environmental impacts as mercury is a toxic heavy metal that bioaccumulates and biomagnificates in the environment. Volcanic emissions also release significant amounts of trace gases, such as carbon monoxide (CO), carbon dioxide, and methane, and we have found genes encoding enzymes responsible for the oxidation of CO in particular.

The enzyme responsible for CO oxidation is the carbon monoxide dehydrogenase (CODH). This enzyme in our model organism (Oligotropha carvoxidovorans) contains a unique active site composed of a molybdenum/copper bimetallic centre. Mercury-resistant bacteria harbour the mer operon that includes merA a mercury ion reductase, which catalyses the conversion of Hg2+ to Hg0. In this PhD proposal, we hypothesise that mercury resistance genes are widespread within bacterial populations and that the mercury reductase, which also contains copper sites, might compete with CODH for available copper and downregulate CODHs, which will decrease CO uptake. This will have negative consequences for atmospheric pollution, as CO concentrations will be higher when mercury concentrations are high.

In this DTP project, the student will determine how mercury exposure affects CO dehydrogenase activity and expression, and whether exposure to Hg alters the regulation of CO oxidation pathways in CO-oxidising bacteria. This will establish how metal stress influences microbial energy metabolism and the regulation of competing metal-dependent processes.

The student will join sampling campaigns in Italy, prepare microcosm incubations and learn interdisciplinary techniques including qPCR, gas-chromatography, enrichment and isolation of bacteria, proteomics and metagenomics.