Protocells artificial cells that are active and mimic living cells by moving and that is biocompatible and active are now possible using an improved method developed by Penn State researchers.

Living cells are difficult to grow in the laboratory, so researchers sometimes work with synthetic cells, but these have had research limitations because they lack real cell characteristics.

One of the challenges of cell research is it’s sometimes very hard to run controlled experiments on a?cell’s motility, especially due to surface enzyme activity.

The research team developed a simple way to make an artificial cell that doesn’t do everything a regular cell does, like reproduce, have genetic mutations or anything like that, but it moves. That’s important because how cells move understood, especially how enzymes’ activity play into cell movement.

The team’s protocells used to investigate how the activity of natural enzymes like ATPase can propel the active movement of the protocells.

The biochemical process of the ATPase enzyme involves the conversion of ATP (adenosine triphosphate) into the product ADP (adenosine diphosphate). ATP is a complex organic chemical that provides energy for living cells and ADP is an organic compound that plays an important role in how cells release and store energy.

Attempts at similar experiments in the past decade had the enzymes incorporated inside of micron-sized sacks called polymeric vesicles or tethered onto the surface of hard particles.

In the research team’s experiments, the protocells have actual artificial membranes composed of an occurring lipid called phosphatidylcholine. ATPase enzymes incorporated into the membrane.

Quite, the movement of the protocells dropped at a high concentration of ATP researcher said.

According to the researchers, this was as counterintuitive as pressing an automobile’s gas pedal and having the vehicle slow down. After performing comprehensive control experiments, the researchers concluded that when ADP concentration is high, it may bind to the ATPase and suppress the substrate ATP activity, causing reduced motility.

A key challenge is to estimate the mechanical forces that drive the protocell movement, and to discover changes in the enzyme structure during that process, Researcher said, Knowing that structure-function relationship for the movement of the protocells will enable their design for potential in vivo applications like medical sensing and lab analysis.