|Jadavpur University, Kolkata, India (2008)
|Jadavpur University, Kolkata, India (2010)
|Indian Association for the Cultivation of Science, Kolkata, India (2016)
|Cornell University, USA (2016-2019)
|Assistant Professor (in Chemistry)
|Abhedananda College under Burdwan University, India (Aug 2020 - March 2021)
|MPI CEC (April 2021 - Oct 2022)
|MPI CEC (since Nov 2022)
# - equal contribution
Time to wish everyone Happy Holidays. Merry Christmas and an advance Happy New Year from us to all of you. We also take this opportunity to thank everyone for their help and support this year.
Time to bid farewell to two group members. Maria is moving on to her next postdoc at Karlsruhe University and Atharv is returning to India after completing his internship with us. Best wishes to both of them.
Guru and Kushal completes a ESRF beamtime. Thanks to Maria Chrystina for flying down from Greece to help them in the beamtime.
We welcome two student assistants in the group, Mr. Marcel Blawat and Ms. Louisa M Clauß. They are BS students at Univ of Duisburg-Essen and Bochum Univ, respectively.
Gursahib, Chris J, Serena, and Kushal completed a beamtime at the I20 beamline again. This was the follow-up time from their July trip. Now it is time to dive into all the data that was collected.
Mr. Atharv Ravi Thakare, from ICT Mumbai-Bhubaneswar, India, joins our group for a short internship to learn more about Biocatalysis. We thank BMBF, DAAD, and DST-India for sponsoring his stay.
Mr. Gursahib Singh Sethi, from TIFR Mumbai, India, joins the team. He will be pursuing his Ph.D. in our department. We wish him all the best!
Serena, Kushal, and Isis had a beamtime at the I20 scanning beamline at DLS. It was a very nice beamtime with very interesting observations.
The BioLabs went for their annual “Betriebsausflug” on the last day of July. This time it was an indoor golf tournament.
Ms. Elena Marie Böhme joins BioLabs as a technician after completing her apprentice training at MPI CEC. We welcome Elena and look forward to working together.
MPI CEC had an Open Day on 13th May. BioLabs saw a great turnout of people. Some pictures from the event.
Kushal presents his work on Nitrogenase at BITS Pilani Goa, India. Thanks to Dr. Sudipta Chatterjee for the invitation.
Maria, Chris, and Kushal complete a very successful and fun beamtime at Diamond I20. They got assistance from former BioLabs members James and Patri. Thanks to Liqun for the constant online support.
In Nature metalloenzymes carry out some of the most fundamental chemical reactions (including dinitrogen reduction to ammonia, hydrogen production, reduction of carbon monoxide/dioxide, methane oxidation to methanol etc.) at very high catalytic rates and with very high efficiency. In spite of the importance and pertinence of the above-mentioned chemical conversions in energy research, there are significant knowledge gaps in the mechanisms by which these enzymes carry out their respective reactions. In metalloenzyme catalysis, earth abundant metals are of special relevance as metalloenzymes use them in their active sites. Intrigued and inspired by these metalloenzymes, our group is trying to learn the role of metal active sites and their surrounding coordination spheres in the mechanism of the fundamental chemical transformations (Figure 1A), a particular focus is to generate and stabilize the intermediates involved in these transformations. We use a combination of biochemical, biophysical, electrochemical and spectroscopic (UV-Vis, IR, EPR, Mössbauer and X-ray based (XAS and XES)) techniques to provide a complete picture of the catalytic active site and the involvement of the neighboring residues and establish a structure-function relationship.
Almost every metalloenzyme, in addition to the catalytic active site, involves additional metal clusters/sites which act as structural sites or are involved in electron/substrate transfers to the active site. Some examples of the additional sites are the 4Fe-4S clusters in Hydrogenases or the unique 8Fe-7S cluster, known as the P-cluster, in N2ases (Figure 1B, C) in addition to the catalytic site (FeMo-co, Figure 1B, C). Moreover, metalloenzymes are often assisted by other metalloproteins for electron transfers and substrate (and co-substrate) diffusions. Our group recognizes the importance of these additional sites/metalloproteins and aims to study them for better understanding of biological catalysis.
A major limitation in studying many metalloenzymes is many times the lack of efficient/suitable heterologous expression systems for their purification. Additionally, their purification from native organisms is not only complicated and time taking but is also of low yield. This especially affects spectroscopic investigations such as X-ray based techniques because it can be very sample intensive. In collaboration with Dr. Decamps group, our group is developing and optimizing recombinant expression systems of metalloenzymes, particularly sMMO, in order to have better yields. sMMO or soluble Methane Monooxygenase (Figure 2) is a metalloenzyme which activates O2 and inserts one atom into an unactivated C–H bond of methane to yield methanol (CH3OH). Our biochemical approaches will be key for enabling advanced spectroscopic studies within our group and more broadly within the Department of Inorganic Spectroscopy, which should ultimately shed light on the key catalytic intermediates in these important energy converting enzymes.
The “Metalloenzyme Mechanistic Explorations” (MeME) team is always looking for highly motivated and dedicated Bachelor, Master or PhD students and Postdoctoral researchers who are interested and would love to work with proteins and inorganic spectroscopy. If you wish to join the team, please contact Dr. Kushal Sengupta with your CV and cover letter.