Studying an important piece of the cellular energy production puzzle

With a bachelor’s degree in biotechnology and a master’s scholarship from the University of Gothenburg, Arpitha Kabbinale arrived in Sweden in August 2018. 

- That was my first time I’d travelled outside India. It was all so exciting, and I took photos of everything I saw in Gothenburg. I’ve deleted a lot of those photos now, because I see the places pretty much every day. 

A seed for the future was planted in her early teenage years in the Indian state of Karnataka.  

- When I was at school, I found out that you could do research studies. I felt straight away that that was something I could do. 

Arpitha Kabbinale completed her master’s degree in molecular biology at the University of Gothenburg, specialising in genomics and systems biology, during the COVID-19 era. Restrictions on international travel made it difficult for her to return to India. Instead, she completed a placement in biophysics at Chalmers University of Technology. She was then accepted as a PhD student at the Department of Chemistry and Molecular Biology at the University of Gothenburg in spring 2021. 

Studying structure and process 

Arpitha Kabbinale’s thesis includes studies of a large protein, the enzyme complex cytochrome c oxidase (c oxidase). This protein is also known as Complex IV and is a key player in the process that takes place just before energy, in the form of ATP, is released in our cells. ATP, adenosine triphosphate, is required for all the processes performed in the body. 

- I’m investigating the protein structure of cytochrome c oxidase in three-dimensional view. Data are collected by means of the X-ray crystallography method, and I’m using spectroscopy as well. The aim of all this is to provide as complete a picture as possible, says Arpitha Kabbinale. 

Examining both structure and process 

Each cell contains mitochondria, the cell’s energy factories. These take nutrients from food and oxygen from the air that we breathe and turn them into energy in a form that can be used by the cells in the body.  

The enzyme cytochrome c oxidase pumps protons (hydrogen ions) across the inner membrane of the mitochondria, forming water and energy. This is required so that ATP can then be produced. 

- Illuminating protein crystals with X-rays provides a diffraction pattern which, in turn, can generate a protein structure. We collect data in very short sequences, one millisecond, ten milliseconds, so that we can see how the reaction continues. It’s like a slow motion film where we can see and understand how protons swap places. 

Hence Arpitha Kabbinale is exploring how cytochrome c oxidase behaves throughout the entire process, and what its structure looks like at the atomic level.  

The protein is taken from the bacterium Thermus thermophilus, a model organism commonly studied in systems biology. Both protein solutions and protein crystals are used in the spectroscopy studies.  

- We’re doing basic research, but anything we discover may turn out to be important in the future – in medicine, for example. 

Singing in her spare time 

Arpitha Kabbinale was initially fascinated by the autumn and winter, and the cold of Gothenburg. But one dark October, she felt she needed to switch off for a while and meet new people. She has always been really interested in singing and music. She heard about the Dream Orchestra at Betlehemskyrkan, the Church of Bethlehem, in Haga and joined the choir. 

- The Dream Orchestra began in 2016 and was intended for vulnerable children and young people. It’s now made up of students from eighteen countries. I love being part of the choir and Betlehemskyrkan; children play games, play instruments and sing. There’s a very warm, informal atmosphere. 

The research group to which Arpitha Kabbinale belongs has also become something of a family. 

- We’re working on different projects, but we all support and motivate one another. Doctoral students are very much alone with their studies, and it’s nice to get some encouragement when things are slow.