<p>Uric acid is the end-product of purine catabolism. In recent years, economic growth and development have significantly improved accessibility to high-purine foods. The increased consumption of foods such as red meat and seafood is directly associated with a higher prevalence of hyperuricemia. Hyperuricemia can lead to the formation of urate stones and gout, and serves as an independent risk factor for hypertension, chronic kidney disease, and cancer. Adverse side effects have been identified for existing treatment methods, which confirm the need for a safer uric acid-lowering treatment with no adverse side effects. Our project introduces exogenous uricase as a novel treatment method. We utilized molecular cloning technologies to insert the gene encoding for urate oxidase into E. Coli, while incorporating the modified probiotics into everyday edibles such as yogurt and freeze-dried powder. Additionally, our design incorporates both a sensory and suicide system to avoid polluting the genetic pool of other species caused by the potential escaping of genetically edited E.coli. To summarize, our project is associated with various sustainable benefits and does not include any adverse side effects.</p>
<p>There is an urgent need for a simple and efficient device to address the escalating issue of microplastic
pollution in the oceans. This device should be characterized by ease of operation, strong
sustainability, high collection efficiency, and minimal impact on marine ecosystems. We aspire to
utilize this device comprehensively to combat microplastic pollution in the oceans, thereby preserving
the health and stability of marine ecosystems and leaving behind a cleaner and brighter marine
<divclass="article-desc-sub-title"id="b1">Purines and uric acid </div>
<divclass="descrption-article-text">
<p>Purines are chemical compounds normally produced in the human body or can be found via the intake of high-purine foods and drinks (eg. meat products). Uric acid is the end-product of purine catabolism and is excreted via the gut and kidneys. </p>
<p>The device we've developed is designed to efficiently process microplastics in the oceans and surrounding
rivers and lakes that are challenging to collect manually. Leveraging biotechnology, we immobilize
genetically modified Escherichia coli on cellulose fibers, effectively capturing and removing
microplastic particles from the marine environment. Furthermore, this device is highly efficient,
environmentally friendly, sustainable, and reusable, aiming to minimize disruption to marine ecosystems
<p>In cases of abnormal metabolic activity, the kidneys cannot eliminate uric acid efficiently, which results in high uric acid levels<spanclass="italics">(Serum uric acid concentrations greater than 6 mg/dL for females, 7 mg/dL for men, and 5.5 mg/dL for youth (under 18 years old) are defined as hyperuricemia[1]).</span></p>
<p>Certainly, my apologies for not including the editing. Here's the translated and edited version:</p>
<p>Hyperuricemia leads to the formation of gout, a form of inflammatory arthritis. When high uric acid concentrations accumulate within the blood, they will precipitate to form needle-like crystals and urate stones. These crystals trigger inflammation, acute pain in the joints, and redness and swelling. </p>
<p>At the outset, we considered directly adhering the engineered bacterial strains to cellulose fibers and
releasing them into the water. However, our laboratory's safety supervisor, Professor Chao Shen from
Wuhan University, cautioned us that this approach could potentially result in genetic leakage, thus
raising significant safety concerns. Subsequently, we explored the possibility of using bacterial
membranes to encapsulate the engineered bacteria before introducing them into the water. Nonetheless,
experts pointed out that this method would significantly reduce the volume of water treated.</p>
</div>
<divclass="descrption-article-text">
<p>Hyperuricemia is also an independent risk factor for hypertension, diabetes, cancer, and mortality. Other complications include chronic kidney disease, and an increased risk of heart attack and stroke. </p>
<p>Consequently, we made the strategic decision to develop a hardware device capable of effectively
preventing bacterial leakage while simultaneously optimizing water treatment efficiency. This design
ensures that our engineered bacteria can efficiently degrade plastic waste in open water bodies.</p>
<p>In recent years, economic growth and development have significantly improved accessibility to high-purine foods. The increased consumption of foods such as red meat, seafood, and alcoholic beverages is directly associated with high uric acid blood levels and a higher prevalence of hyperuricemia in both China and abroad. </p>
<p>In regions where wastewater flows at a sluggish pace, only a small portion of the water may pass through
our device over an extended period. Unfortunately, this results in suboptimal wastewater treatment
efficiency. To address this challenge, we opted to incorporate an impeller into our device to accelerate
the flow rate of wastewater. The impeller requires an electrical power source, and after considering
various factors such as cost-effectiveness and environmental sustainability, we determined that
low-pollution, cost-effective solar panels were the most suitable choice for power generation.</p>
</div>
<divclass="descrption-article-text">
<p>According to "White paper on trends of Hyperuric acid and gout in China, 2021" [3], a clear trend of hyperuricemia diagnosis is demonstrated among younger generations. The prevalence of hyperuricemia and gout in China currently stands at 13.3% and 1.1%, respectively, with nearly 177 million individuals diagnosed with hyperuricemia and 14.46 million with gout. </p>
<p>To implement this, we replaced the top section of the device with solar panels, positioned the impeller
within the device, and securely connected it to the solar panels. Recognizing the intermittent nature of
solar power generation, particularly on overcast or rainy days, we incorporated a battery into the
system, seamlessly linked to the solar panels. This ensures uninterrupted device operation, even when
<p>In addition, we surveyed 367 individuals, inquiring if they had a family member or friend diagnosed with hyperuricemia. Surprisingly, 57.92% of the respondents answered with a "yes". These confirm that hyperuricemia has become a significant factor affecting national health and cannot be ignored. </p>
<p>The exterior of the cylindrical device is constructed from specially designed plastic, featuring a
grid-like array of strip filters that effectively screen out impurities.</p>
<pstyle="margin-left: 3em;">This first treatment method involves the usage of allopurinol to inhibit xanthine oxidase and subsequent uric acid production. Xanthine oxidase is an important enzyme that catalyzes the last step of purine catabolism: the oxidation of xanthine to uric acid. If xanthine oxidase is inhibited, uric acid production will cease. According to research articles, this method is associated with adverse effects such as allergic dermatitis (affecting 0.4% of users) and drug fever (affecting 10%-15% of users). </p>
<p>Located at the bottom are genetically modified Escherichia coli strains that have been immobilized onto
cellulose fibers. This configuration is designed for the purpose of microplastic filtration.</p>
<pstyle="margin-left: 3em;">This second treatment method involves the utilization of uricosuric agents probenecid, sulfinpyrazone, or benzyl bromide to accelerate uric acid production and excretion via the kidneys or gastrointestinal tract. This method may prove unsuitable for existing patients with gout or renal insufficiency, as it can cause kidney functional damage or can exacerbate kidney stones.</p>
<p></p>
</div>
<divclass="descrption-article-text">
<p>To summarize, the development of a safer treatment method with no adverse side effects or disadvantages for patients diagnosed with hyperuricemia is urgently needed. This is the issue that we addressed and responded to, and is the primary objective of our project. </p>
<p>After designing the initial device, during discussions with staff from the Wuhan East Lake Management
Office, we identified several issues with the hardware.</p>
<p>We surprisingly discovered that hyperuricemia is a disease that is exclusive in humans but absent in most animals. By conducting a series of researches, we were informed that this disease is due to the absence of a specific enzyme urate oxidase, which prevents the build-up of uric acid. The absence of urate oxidase in the human body stops the purine degradation pathway at the stage of uric acid, while in other organisms uric acid can be further degraded to a soluble end product that does not cause stones in the joint. This gives us the idea that the problem can be solved if the enzyme urate oxidase, also known as uricase, can be added to and produced regularly within the human body. </p>
<p>Firstly, we failed to consider the stability of the hardware on the water's surface. In real-world
testing, it frequently capsized. Secondly, some debris outside the hardware device was not effectively
managed. Thirdly, the membrane-like filter cotton was prone to damage.</p>
</div>
<divclass="descrption-article-text">
<p>We have also learned that while two-thirds of uric acid is excreted from the kidneys, one-third is excreted through the intestines [4]. Being further inspired by the recent year cases of "living medicine," a term that describes the foundation that microbes provide for humans to solve catabolic problems, we decided to adopt a similar method to allow uricase to be produced within the intestines. </p>
<p>To address the feedback from users and draw inspiration from a swimming pool debris handler, we have
designed the second-generation hardware system.</p>
<p>Our project introduces exogenous uricase as a novel treatment method for hyperuricemia. </p>
<p>We utilized molecular cloning technologies and inserted the exogenous gene<spanclass="italics">(<strong>E. coli</strong> DH5α/pMD18T)</span>encoding for urate oxidase into the bacteria E. Coli cloning vector<spanclass="italics">(<strong>E. coli DH5α/pSB1A3-mRFP</strong>)</span>through plasmid transformation. We subsequently incorporated the modified probiotics into yogurt and freeze-dried powder edibles. </p>
<p>To address the first issue, we incorporated three floatation devices, significantly enhancing the
hardware device's stability on the water's surface, as illustrated in Figure 2.</p>
<p>Uricase, or Urate Oxidase, is a copper-containing oxidase responsible for the hydrolysis of insoluble uric acid to water-soluble allantoin and 5-hydroxlsouric acid in the purine degradation pathway. This enzyme does not exist naturally in the human body. [5]</p>
<p>To tackle the second problem, we introduced a larger debris collection frame. This frame is capable of
simultaneously capturing larger particulate pollutants, effectively addressing the challenges posed by
both microplastics and larger debris, as depicted in Figure 3.</p>
<p>Our project uses Escherichia Coli Nissle 1917 as the chassis cell. It is a remarkable probiotic bacterium that has a unique profile concerning fitness factors in the absence of any virulence factors. More recently, EcN, due to its innocuous nature, has been used as a delivery vehicle for vaccines, cytokines, and other substances. [7]</p>
<p>In response to the third issue, we modified the membrane-like filter into a porous structure. This
alteration not only improves water flow permeability but also mitigates the likelihood of breakage, as
<p>Our project efficiently reaches the target of our goal to "develop a safer treatment method with no adverse side effects or disadvantages for patients diagnosed with hyperuricemia", as it is associated with the following benefits: </p>
<p>The overall device consists of an enclosure, a water pump (1), floatation devices (2), a filter basket
<li>Unlike other drugs, our modified Escherichia coli will continuously release urate oxidase within the intestines. The coordinated intestinal flora microecology will play a positive, long-term role in regulating human health. </li>
<li>The production of uric acid within the intestines can be directly decomposed without the involvement of drug absorption and metabolism within the body. It performs molecular diffusion along its concentration gradient, where uric acid within the bloodstream can backflow into the intestines and undergo direct decomposition. It does not need to go through the human metabolic system. </li>
<p>Improvements were made based on our original gene circuit design, as in the process of conducting integrated human practice, one judge pointed out one of the possible problems of our design on the CCiC conference: As the genetically edited escherichia coil moves out with egestion, there's a possibility of them escaping into the environment and causing pollution to the genome of other species. As a response, we collected information from the igem registry and read research papers to redesign our genetic circuit, presenting the following figure as the final version. </p>
<p>In the operational process, we place the cellulose fibers containing engineered bacterial strains into
the device and then deploy it into the water. Floatation devices ensure that the equipment remains
afloat on the water's surface. Once connected to a power source, the water pump is activated. It draws
in the upper-layer water (where plastic accumulates) into the device, and this water is treated by the
cellulose fibers carrying the engineered bacterial strains. The engineered bacteria initiate the
degradation of PET (a common plastic), and the purified water is discharged from the bottom of the
<p>HucR is a gene that transcribes a protein that can combine with Uric acid and the Huc promoter at the same time. If Uric acid is present, the protein encoded by HucR forms a complex with uric acid that cannot bind to the HucO promoter region, thereby allowing the transcription of HucO. If Uric acid is not present, the protein encoded by the HucR gene will bind with the promoter region of HucO, inhibiting transcription of the following sequence. </p>
<p>Note: We are fully aware of the importance of biosafety. Even under controlled conditions, taking
engineered bacteria out of the laboratory is a highly irresponsible act. Therefore, in all videos
demonstrating the operation of this hardware in open environments, engineered bacteria have not been
<p>The uaZ gene produces urate oxidase extracted from aspergillus flavus, which catalyzes uric acid into a final, more excretable form of allantoin. </p>
<p>After designing this device and engaging in discussions with staff from the Wuhan East Lake Management
Office, we identified certain issues and subsequently made improvements to the equipment.</p>
</div>
<divclass="descrption-article-text">
<p>The higher the concentration of uric acid, the more this enzyme is produced. </p>
<p>1. Providing power sockets at every lakeside location is impractical. Therefore, we have integrated solar
panels into the device, allowing it to operate independently and reducing its dependency on conventional
power sources. We believe this innovation will make our device more sustainable and applicable to a
<p>The cI gene (BBa_C0051) is responsible for producing the protein 1F39, which can bind simultaneously to operators OR and OL, and arrange the DNA into a loop. This prevents transcription. </p>
<p>The CI gene was stated in references articles and the IGEM registry as efficient but not oversensitive, so it suits the need that the suicide system will not be activated due to environmental fluctuations of Uric Acid concentration.</p>
<p>2. When deploying the device on open water surfaces, without proper anchoring, the pollution treatment
equipment itself might become a new source of pollution. To address this concern, we have implemented an
anchoring system, allowing the device to be securely anchored within a specific range along the
<p>The E gene produces a suicide protein 4EPI (BBa_K112806) extracted from Escherichia virus T4. This T4 Endolysin helps degrade the plasma membrane from its host. </p>
<p>1. Anchor Rod Schematic</p>
</div>
<divclass="article-desc-sub-title"id="b9">How the circuit systematically works</div>
<divclass="descrption-article-text">
<p>We incorporated a uric acid sensor, which detects the concentration of uric acid. The higher the concentration of the uric acid, the more efficiently the sequence will be translated. The uric oxidase is located directly after the uric acid sensor, meaning more oxidase will be produced when there is more uric acid. </p>
<p>2. Actual Anchor Rod Photo</p>
</div>
<divclass="descrption-article-text">
<p>We also included a suicide system, with a CI repressor repressing the translation of the suicide protein 4EPI. When the uric acid concentration drops, meaning our bacteria are outside of the body, the repressor will deactivate, and the suicide protein will be produced, killing the bacteria. </p>
<pstyle="text-indent: 0;margin-left: 2em;">[1] Gois, Pedro Henrique França; Souza, Edison Regio de Moraes (2020-09-02).<ahref="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8094453"> "Pharmacotherapy for hyperuricaemia in hypertensive patients"</a>. The Cochrane Database of Systematic Reviews. 2020 (9): </p>
<pstyle="text-indent: 0;margin-left: 2em;">[4] Yun Y, Yin H, Gao Z, Li Y, Gao T, Duan J, Yang R, Dong X, Zhang L, Duan W. Intestinal tract is an important organ for lowering serum uric acid in rats. PLoS One. 2017 Dec 21;12(12):e0190194. doi: 10.1371/journal.pone.0190194. PMID: 29267361; PMCID: PMC5739491.</p>
<p>2. Secure one end of the rope to the anchor rod.</p>
</div>
<divclass="descrption-article-text">
<pstyle="text-indent: 0;margin-left: 2em;">[5][6] MLA. Nelson, David L. (David Lee), 1942-. Lehninger Principles of Biochemistry（8th Edition). New York :W.H. Freeman, 2005.</p>
<p>3. Secure the other end of the rope to the hardware device.</p>
</div>
<divclass="descrption-article-text">
<p>[7] M. Schultz, J.P. Burton, Chapter 5 - Escherichia coli Nissle 1917, Editor(s): Martin H. Floch, Yehuda Ringel, W. Allan Walker, The Microbiota in Gastrointestinal Pathophysiology, Academic Press, 2017, Pages 59-69, ISBN 9780128040249, <ahref="https://doi.org/10.1016/B978-0-12-804024-9.00005-7.">https://doi.org/10.1016/B978-0-12-804024-9.00005-7.</a>(<ahref="https://www.sciencedirect.com/science/article/pii/B9780128040249000057">https://www.sciencedirect.com/science/article/pii/B9780128040249000057</a>) </p>
<p>This anchoring system ensures the stable positioning of the device and prevents it from drifting or
causing any unintended environmental impact.</p>
</div>
<divclass="article-desc-title"id="a9">Cost Breakdown for Microplastic Treatment Device Components</div>
<divclass="descrption-article-text">
<p>This cost breakdown presents an estimate of the expenses associated with the key components required to
build a Microplastic Treatment Device. The device aims to address the issue of microplastic pollution in
open water bodies while remaining cost-effective. Each component's cost range is provided, along with
potential suppliers to help teams find the most affordable and suitable options. The total estimated
cost falls within a budget of $47 to $85, ensuring that the device remains affordable for various
