Robotic microbial protein analysis

Microorganisms have potential as living factories for manufacturing drugs and biochemical products. Rapid mass screening methods are needed to identify new species. A new robotic system also provides useful data for genetic engineering.

There are so many species and subspecies of bacteria and fungi that remarkable discoveries are made every day. Biologists are keen to exploit their ability to produce compounds that could be of use to humans, for instance in medicine, using either native or genetically modified organisms. A new approach to the classification of micro-organisms, i.e. distinguishing between related species, involves analyzing some of the proteins they contain. A mass spectrometer records their “fingerprint”: As proteins and protein fragments fly through the instrument’s vacuum chamber, a computer analyzes their time of flight to determine their molecular weight and electrical charge. The pattern produced by an unidentified sample is compared with known patterns. Naturally, this high-speed analysis technique depends on the availability of a database containing the typical profiles of proteins found in the maximum possible number of microorganisms.

Despite the automation of many routine laboratory tasks, this type of analysis still requires a great deal of manual input. Especially when working with pathogens that present a risk to human health, strict safety precautions have to be observed during sample preparation. This is not the case with “Mirob”, a new robotic system for rapid microbial analysis. Working autonomously, the robot extracts the samples under the guidance of a camera and image processing software, and transfer them to the mass spectrometer. An important aspect of the continuous process is material flow control, as Oliver Lange of the Fraunhofer Institute for Factory Operation and Automation IFF in Magdeburg explains: “The camera records the label on each Petri dish and simultaneously reads its barcode. The computer links these data with the analysis result when it is output a few minutes later. In this way, we can be certain of avoiding the mix-ups that occasionally spoil a whole series of measurements.”

As well as coordinating the project, which was sponsored by the German research ministry BMBF as part of its “Research for the Production of Tomorrow” program, Oliver Lange worked on sensors, control system and image processing with colleagues from the Institute of Micro and Sensor Systems at the Otto-von-Guericke University of Magdeburg. The engineering side of the Mirob project was also handled in Magdeburg, by local companies engelke engineering art and Symacon GmbH. Another project partner was Proteome Factory AG. The first robotic system was recently sent to biotech firm Anagnostec for testing. Marketing is due to start soon.