Introduction

The well being of others is an important factor in all scientific work. Many scientific advances of recent years have been pioneered in order to improve the lives of those in the community, as well as across the world. Synthetic biology is an emerging scientific field that may hold the key for a new frontier of technological advancement, but with a new field comes new safety concerns, new security issues, and an entirely re-inspired view on conduct both in and outside of the lab.

It is important to step back and look at the potential health and safety aspects of any synthetic biology project, in order to understand and improve our knowledge of basic biosafety and biosecurity practices.

Lab Safety

Our project involves live bacteria, and therefore, poses a threat to members of our lab if not proper precautions are not taken. Our E. coli will have been designed to intracellularly produce antimicrobial peptides (AMP) upon entry to the small intestine, inducing E. coli cell death. If some of our E. coli were to be accidentally ingested by a member of the lab, assuming the bacteria survive the acidity of the stomach, they would burst within the gut. Because the AMP in question is protegrin-1, which is derived from humans, it will not attack the membranes of the host’s cells; however, the destruction of E. coli, a gram-negative bacterium, will result in the release of endotoxins trapped within the membrane, potentially inducing septic shock. In order to minimize the risk of contamination, gloves and lab coats will be worn at all times to prevent accidental contact. Furthermore, we have received documents explaining our lab safety protocols in detail, and copies will be kept both in the lab alongside the copies we bring home.

Biosafety

The risk of releasing genetically-engineered microorganisms (GEMs) from the lab is a growing concern amongst synthetic biologists. Upon accidental release, our E. coli would need to find food to survive in outside world, and since this strain is both non-pathogenic, as well as endemic to the human gut, the chances of it replicating uncontrollably outside the lab are slim, but not impossible. If ingested, the E. coli would not pass through the population due its programmed cell death within the body. If our bacteria were to find food and multiply, potentially on a foodstuff to be eaten by humans (e.g. German cucumbers), then mass ingestion by an individual could result in endotoxin-induced septic shock. An important biological function to address in the presence of GEMs is horizontal gene transfer, where one bacteria transfers part of its DNA to another. E. coli would travel to the gut of an individual, and could potentially transfer the AMP gene to endemic gut flora. In our specific case, where the only altered gene is one that induces cell death, transfer of that gene to other bacteria would result in reduced fitness for the gene recipient. Not only that, but AMP production would happen upon entry to the gut, and these proteins act intracellularly not only to disrupt the membrane, but also to bind to important cellular machinery and inhibit the process of cellular growth. As the chance of horizontal gene transfer is inhibited along with decreased cellular functionality, the odds of in vivo gene transfer occurring are minimal. Released bacteria interacting with the environment is also a cause for concern. If a GEM is released into an environment that suites colonization, it can potentially out-compete other species into extinction. GEMs have combinations of genes that do not occur within nature, and this can result in new emergent properties that can complicate quantifying the level of risk from release. It is also important to note, however, that GEMs are commonly less fit than their wild-type counterparts, reducing the chance of a successful colonization. Horizontal gene transfer is a concern, but again, the reduced fitness of the gene recipient combined with the decreased functionality of plasmid transfer in the presence of AMPs makes the likelihood of repeated horizontal gene transfer.

Biosecurity

What is even harder to quantify is the security risk posed by our GEM. Rogue individuals, groups, or states may use synthetic biology to cause harm to others for various personal gains, and its imperative that our project is viewed through the lens of a security risk, in order to better understand exactly how dangerous our project may be. Our project is essentially creating and mastering a tool: the controlled self-induced lysis of a cell using intracellular AMP production. Our team is using that tool as a potential method of drug delivery (amongst others discussed on our wiki), but tools are utilized to fulfill the aims of the user. Our project could infact even be implicated in reducing risks posed by GEMs by allowing scientists to control there viability out with the lab, either by using a negatively controlled promoter dependent on a substance only presented to the bacteria in the lab or using a positive promoter to cause the bacteria to self destruct when in the presence of some chemical found widely in the natural environment.

Since we are altering a non-pathogenic E. coli strain to die in the presence of its natural environmental niche (i.e. the human gut), the bacteria will be less pathogenic, less of an environmental threat than in its wild-type form, and less of a security concern. This is no accident, we were careful to engineer our design to minimize risk right from the outset. The only cause for concern may be the drug our bacteria will release upon self-lysis, but because what we are performing are simply proof of concept experiments, the intracellularly-produced his-tagged green fluorescent protein (GFP) should not be cause for concern. Any data we collect that presents point to the contrary will be posted on both our wiki, as well as the MIT Registry of Standardized Parts website.

St Andrews Safety

Our institution operates under the guidelines set by the University of St Andrews Biology Health and Safety Committee. We have not discussed our project with them, nor do we plan to, as we feel that the guidance of advisors who are seasoned with past iGEM competition experience should suffice. A copy of the School Health and Safety Policy written by the Health and Safety Committee is posted and available in every lab on campus. We received basic lab training at the start of the 10-week iGEM process, including sterilization protocols, bench cleanliness, chemical and bacterial waste disposal, how to handle dangerous chemicals (including ethidium bromide), and standard laboratory conduct. Compounded with the lab training most of us had received throughout our course of study, we felt we were more than prepared to handle the lab in an appropriate manner.

The United Kingdom abides by the laws set out in the Control of Substances Hazardous to Health ( COSHH)