Safety Concept

Safety is paramount in science; thus, during the entire project safety was taken very seriously. In general we split the safety into three major areas: First, the COVID-regulations for personal safety and to reduce the risk of infection during the iGEM-times to a minimum. Second, we have certain rules and regulations for the laboratory work. Third, we had specific regulation regarding the microorganisms used and for potential implementation.

Safety during SARS-CoV-2

In Austria a general “3G” regulation was established. The 3G rule means that one is either vaccinated (3x), recovered or PCR-tested negative valid for 48 hours. The university also had certain rules such as a safety distance of 2m if possible and not less than 1m. Wearing of an FFP2-mask at all rimes was mandatory. Furthermore, we as a team agreed on PCR testing ourselves at regular intervals to maintain a very low risk of infection. Also we agreed on a “no-show policy” if someone had the slightest symptoms or wasn’t feeling well.

Safety in the laboratory

During the lab work we followed the lab work regulations by wearing a lab coat, safety glasses for work with hazardous liquids and wearing cryo or thermo gloves while working with frozen or hot materials, such as samples from liquid nitrogen tanks or autoclaved materials. We also had some mandatory introduction to certain devices such as large autoclaves and centrifuges. A laboratory technician position for establishing a safe biowaste disposal and supplying sterilized lab glassware and tips was also created. To avoid any health problems to become life threatening, we agreed on working in the lab only if at least two persons were present at the same time. Sterile work was always performed under a hood. No gas was used, so the valves were switched off.

Microorganisms and unsafe release

Microorganism strains used in the project were Escherichia coli (gram negative bacteria, prokaryote), Pichia pastoris (yeast, eukaryote) and Synechocystis sp. PCC 6803 (cyanobacteria, prokaryote). All strains are defined as biosafety level 1 organisms. This means that organisms that “escape the lab” are not pathogenic and also not able to live outside lab conditions. As in our potential implementation, incorporation of GMOs in our material is a possibility, we discussed various levels of safety regarding safeguarding unregulated propagation of GMOs.

Biosafety Level 1: Expression host

As mentioned before, all of our organisms and strained were risk group 1 organisms, thus on the iGEM White List. As our material can and should be used outside of the lab, this was the first step to curb potentially disastrous consequences.

Biosafety Level 2: Entrapment of GMOs

While we didn't include GMOs in our material during our work in the lab, an incorporation of such organisms in this material can be considered for various reasons. The primary safeguard in such a scenario is the physical entrapment of the GMOs in the brick material. We use biopolymers such as gelatin and spider silk for the purposes of creating a hydrogel, which, upon drying, entraps the GMOs, making it harder for the organisms to escape.

Biosafety Level 3: Auxotrophy

Brick and building material, naturally, can break or brittle. This is why a potential break-free is a scenario we need to think about. Negative selection pressure through auxotrophy would ensure that GMOs in our material can not proliferate as efficiently as wild type yeasts and cyanobacteria. The artificial metabolic burden through the introduction of plasmids would be a strategy to prevent overgrowth and uncontrolled spread.

Biosafety Level 4: Kill-Switch

For a potentially global use of Pichitecture, auxotrophies may not be enough. An establishment of a kill-switch is necessary to ensure successful containment of GMOs in our material. Kill-switches can be explored depending on where the material may be used: atmospheric oxygen, light exposure or decreased temperature are potentially effective approaches that will be explored in our collaborative work with building and construction firms, as we can tailor the potential kill-switch to their needs.