RUI: Collaborative: A REAL Approach to Investigating Bacterial Degradation of PET Plastic Waste

减少、再利用和回收计划很重要，但不足以解决我们星球面临的大规模塑料污染问题，因此本研究的重点是我们环境中发现的塑料的生物降解。为了创造一个更加循环的塑料经济，研究人员之前分离出了一个细菌群落，总共有五种，可以降解聚乙烯对苯二甲酸乙二醇酯（PET），这种材料用于制造塑料水瓶。总的来说，这个联合体比单独的联合体或物种生长得更快，产生了更多的塑料降解酶活性。研究人员将确定这些观察结果的遗传和生化基础。该合作项目将为本科生和高中生提供旨在完成项目的研究机会。年代的目标。第一代和未被充分代表的少数民族学生将被招募参加这一系列令人兴奋的项目，并为夏季研究提供资金，并在学年期间继续努力。细菌降解PET的遗传基础也将在普通微生物学课程的实验室部分进行研究，以丰富课程内容。土壤细菌对PET塑料的协同降解尚未被探索，但有可能帮助去除目前存在于我们环境中的约63亿吨塑料中的一部分。通过筛选与塑料降解有关的脂肪酶活性，从休斯顿附近的石油污染土壤中分离到3种假单胞菌和2种芽孢杆菌。五种细菌的联合体协同作用，产生更多的脂肪酶活性和降解PET塑料比单个联合体或菌株更快。在KEGG通路数据库的帮助下，研究人员将挖掘这五种细菌的基因组，以了解PET生物降解所必需的代谢途径，并将使用核磁共振识别副产物，将这些数据与遗传信息联系起来。分泌的酶将使用光谱技术进行鉴定。转座子诱变是一种无偏倚的方法，它将确定PET降解所需的脂肪酶、酯酶和生物膜形成的表达和分泌的遗传基础。研究人员还将利用RNA测序，剖析酯键裂解和对苯二甲酸和乙二醇单体完全降解所需的联合细菌的基因调控网络，最终目标是减少陆地和海洋中的PET废物。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Reduce, reuse and recycle programs are important, but are not enough to address the massive plastic pollution problem facing our planet, and thus this research is focused on the biodegradation of plastics found in our environment. Toward creating a more circular plastic economy, investigators previously isolated a consortium of bacterial species, five in total, that degrade polyethylene terephthalate (PET), the material used to make plastic water bottles. Collectively, the consortium grew faster on, and produced more plastic-degrading enzyme activity than individual consortia or species alone. Researchers will determine the genetic and biochemical basis for these observations. The collaborative project will provide undergraduate and high school students research opportunities aimed at accomplishing the project?s goals. First generation and underrepresented minority students will be recruited for this exciting set of projects, with funding for summer research, and continued effort during the academic year. The genetic basis for bacterial degradation of PET also will be investigated in the laboratory portion of a general microbiology course, enriching the curriculum. Synergistic degradation of PET plastic by soil bacteria is unexplored, but has the potential to aid in the removal of a portion of the estimated 6.3 billion metric tons that currently exist in our environment. Three Pseudomonas and two Bacillus spp. were isolated from petroleum polluted soils near Houston, TX, by screening for lipase activity, which has been associated with plastic degradation. The consortium of five bacterial species act synergistically, producing more lipase activity and degrading PET plastic faster than individual consortia or strains. Investigators will mine the genomes of the five bacteria to understand the metabolic pathways necessary for biodegradation of PET, aided by the KEGG pathways database, and will use NMR to identify byproducts, correlating these data with genetic information. Secreted enzymes will be identified using spectrometry techniques. Transposon mutagenesis, an unbiased approach will determine the genetic basis for expression and secretion of lipases, esterases, and biofilm formation necessary for PET degradation. Investigators will also dissect the genetic regulatory network, using RNA sequencing, of the consortium bacteria required for ester bond cleavage and the complete degradation of the monomers terephthalic acid and ethylene glycol, with the ultimate goal of reducing PET waste on land and in our oceans.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.