 Putting cells under pressure, a simple and efficient way to enhance the productivity of medium chain-length polyhydroxyalkanoid in processes with Pseudomonas Putita KT2440. This is a paper that we prepared for biotechnology and bioengineering and is co-authored by Stefanie Folonier, Bernard Henes, Sven Panker and Manfred Zinn, which is myself. So the goal of this paper is to look at the influence of increased pressure on oxygen transfer. Basically, what we want to do is increase high cell density in such fermentations and then have, well, because of higher oxygen need, we would like to have an increase of the oxygen transfer by itself. So what we did, we did first batch experiments and what we could observe is that when we increase the pressure to seven bar, we can achieve dissolved oxygen tension of 680%. However, this has an influence on the specific growth rate and what we could observe is that under such high oxygen tensions, we have a decrease of the growth rate. Nevertheless, when we have a look at the Kibonstadt experiments, we could observe that when we are in a certain range of dissolved oxygen tension, we can have same productivities and also even a little bit higher PHA production. Polyhydroxyalkanoid is a bioplastic, by the way, which is intracellularly accumulated and is of interest for industrial and medical applications. So to conclude, we found that when you control the pressure in a certain range, we can have good productivity and also have oxygen transfer, which is suitable for high cell density fermentations. Actually, we could triple the PHA productivity to 11 gram PHA per liter an hour. Finally, I would like to acknowledge that this work has been sponsored by the Swiss National Science Foundation and also I'd like to thank all collaborators that helped in this project. So I'm looking forward to learn your comments and also what you think of this paper.