Sheffield Championship Poster

The Fatberglars
Synthetic Biology for Everyday Life: A small scale, semi-continuous
bioreactor for the controlled release of FOG degrading enzymes
Student Members: Lara Grew, Mustafa Hussain, Ben Lomax, Ben Madden, Sharan Nanuan, Erika Otaviano, Jianxing Qin, Alexander Simpson
Advisors: Elizabeth Court, Celso Gomes, Charlotte Green, Andrew Landels, Robert Meckin
Instructors: Dr Susan Molyneux-Hodgson, Dr Graham Stafford, Prof Phillip Wright
Our project is aimed at tackling an everyday life issue. We surveyed students at Sheffield University for problems they would like us to solve and
after receiving over 100 suggestions, we chose to tackle the issue of
blocked drains and sewer pipes.
Throughout our project, we committed ourselves to the values of simplicity, integration and standardisation. These were intertwined through our
science, product development, policy and social practices.
Here we present a synthetic biology solution to problem of "fatbergs".
What are Fatbergs?
Fatbergs (Fig. 1.) are large accumulations of fats, oils and greases
(FOGs), hair and other detritus.
These cause blockages in sewer
systems throughout the world.
These have a huge environmental
and economic impact, costing
around £1,000,000 per month to
tackle in London, UK alone.
Figure 1. A fatberg found at Yorkshire
Water’s Hayton Wastewater Treatment Facility, during the team visit.
Figure 2.
SocioBrick Registry
Symbols denote 5 different SocioBrick types that
can be assembled into
constructs, much like BioBricks, to make a SocioBrick construct.
Standardisation is a fundamental strand of the ethos of iGEM that has not been integrated through all
elements of the competition. To make policy and practices more accessible and easier to understand
we have created the SocioBrick Registry: a novel way of characterising and modularising project
components. Teams will be able to select SocioBricks to guide the construction of social research,
policy and outreach activities, using the five SocioBrick types denoted in figure 2.
Policy and Practices
We initially intended to express the thermostable lipase BBa_K258006 and
Our ‘Notions of Responsibility’ report investigates how different groups
a novel keratinase[1] under the PfadR lipid responsive promoter
spoke about responsibility for FOG disposal and sewage network mainteBBa_K861060. Due to changes during the development of the Fatberglar
nance. The report describes a complex array of practices, including recyunit, constitutive expression of enzymes was recling, maintaining customer satisfaction and
The Fatberglar Unit
quired and so BBa_J23110 was used in our final
surrounding FOG disposal. These findings
were integrated into the Fatberglar product deWhilst our keratinase was exported by native E. coli
sign process. The Notions of Responsibility Sosecretion systems, a Type 1 secretion system
cioBrick construct (Fig. 6) was used to structure
BBa_K258008 was necessary to export the lipase
research into attitudes to responsibility.
(Fig. 3).
Figure 6. The Notions of Responsibilty SocioBrick construct
was used to structure research into varying attitudes to
Figure 3. The final constructs that were submitted to the
registry: our constitutively expressed lipase construct
(BBa_K14980001), requiring a pre-existing Type I secretion
module from the registry (BBa_K258008 - shown in figure)
and our novel keratinase (BBa_K1498000).
Figure 8. Concept design for The Fatberglar bioreactor, consisting of an enzyme holding tank, an impeller and baffles
for agitation, and a partially permeable membrane for O2
diffusion. A 0.22 μm filter enables free diffusion of enzymes
without release of GMOs. The bacteria are maintained by a
replaceable slow-release nutrient feed mechanism
Using spectrophotometry (Fig.3) and fluorescence microscopy (not
shown) we found the registry PfadR biobrick to be non-functional. We successfully secreted active lipase (Fig. 4.) and a keratinase pre-protein verified by SDS-PAGE (not shown), which was non-functional (Fig. 5.).
Figure 4. TliA Characterisation: We
demonstrated lipase activity of TliA
using a Rhodamine B plate assay,
which fluoresces under UV with the
presence of degraded triglyceride. Supernatant of cells containing empty
vector was used as a negative control.
Figure 3. Characterisation of PfadR
(BBa_K861060) - results from the
TECAN spectrophotometer indicated
no difference in fluoresecence emitted from the PfadR-RFP and the PfadR
only negative control.
Figure 5. KerUS Characterisation: We
tested kerUS activity using a gelatin
plate assay. A halo following protein
precipitation indicates protease activity. S. aureus was used as a positive
control, E. coli with empty vector was
used as a negative control. KerUS
showed no protease activity.
2010 Sheffield iGEM team developed a lab protocol notation system. We continued to develop
this concept with the intention of further standardising and simplifying lab practice in iGEM
projects. During that process we tested several
iterations of the notation system in collaboration
with the Edinburgh, Cambridge JIC and Valencia_UPV iGEM teams. We arrived at a notation
system that includes colour-coded categories
and hierarchical indentations (Fig. 7), which
makes protocols easier to read and understand.
Figure 7. (A) Key for lab notation and (B)
an example of a protocol written in the
improved lab notation format. This is the
protocol used to create LB.
Product Design.
The Fatberglar is an under-sink unit, designed for the controlled release of
lipase enzyme into wastewater containing FOGs. Prior to the final design,
the Fatberglar went through 5 distinct iterations. These were modified following expert advice and design specifications, with the end user in mind
The final product specifications are size: 1.2L capacity, Cost: < £100 ($150),
maintenance: clean and feed the unit once per month, expected lifespan: 5
years (with replaceable parts). (Fig. 8).
Figure 9. The Product Design SocioBrick was used to structure the iterative design process
during the creation of the Fatberglar unit.
[1] Jaouadi, N, 2013. Biochemical and Molecular Characterization of a Serine Keratinase from Brevibacillus brevis US575 with Promising Keratin-Biodegradation and Hide-Dehairing Activities. PloS one, 8 (10)