X‐linked inhibitor of apoptosis protein (XIAP) is a key prosurvival protein that blocks apoptosis by inhibiting both the intrinsic and extrinsic pathways. Released by the mitochondria when under stress, XIAP is a homodimer, with 2 sets of repeating type I and type II baculoviral IAP domains: BIR1, BIR2 and BIR3, and RING. XIAP has a capacity to block apoptosis by directly inhibiting caspases 3,7 and 9. Second mitochondria‐derived activator of caspases (Smac) is a 184 amino acid chain. Smac antagonizes XIAP by attaching to the BIR3 domain inhibiting the binding of caspase‐9. Synthetic Smac mimetics (SMs) have been designed to duplicate the N‐terminal tetrapeptide (AVPI) or the IAP‐binding motif (IBM). Our model aims to show two BIR3 domain of a homodimer XIAP, bound to the IAP‐binding motif (IBM) of a Smac dimer. Selective antagonism of XIAP, specifically the BIR3 by Smac/SMs or monotherapy is not enough to kill cancer cells, however, it could be combined with immunotherapy, specifically virotherapy. This tricks the immune system to think that the cancer cells have a virus, which stimulates the immune antiviral response and creates an overproduction of immune cells known as a “cytokine storm”, to kill cancer cells. Support or Funding Information The Ashbury College MSOE Center for BioMolecular Modeling SMART Team used 3D modeling and printing technology to examine structure‐function relationships between Smac and BIR3 of XIAP.

Polyethylene terephthalate (PET) is a synthetic polymer made from chemicals derived from crude oil. As a result of the high volume of plastic produced in the world today, only 9% of all plastics have been recycled while the rest is either dumped in the natural environment or incinerated, leading to problems like plastic pollution and overflowing landfills. PET and other polyesters have been accumulating in the Great Pacific garbage patch. The island of trash causes disturbances in the North Pacific Subtropical Gyre food webs and poses threats towards marine species through entanglement and consumption. While the majority of PET is currently recycled mechanically, this method often consumes high amounts of energy, releases harmful by‐products, and results in a loss of material properties in PET, decreasing the intrinsic value of the polymer. There are also few affordable chemical recycling solutions because of PET’s high resistance to biodegradation, which is due to its structural elements such as its aromatic groups and crystallinity that limit polymer chain movement, generate surface hydrophobicity, and limit its accessibility to ester linkages; making it recalcitrant to catalytic or biological polymerization. In 2016, a bacterium called Ideonella Sakaiensis 201‐F6 was found to have the ability to degrade PET at room temperatures via the secretion of two main enzymes: IsPETase and IsMHETase. IsPETase has a penchant for breaking down crystallized PET over other types of polyester using a wide substrate‐binding pocket. The second enzyme IsMHETase is a hydrolase that has an α/β‐hydrolase domain and a lid domain granting substrate specificity. The degradation process begins when the PET hydrolase (IsPETase) cuts the PET polymer into mono(2‐hydroxyethyl) terephthalate acid (MHET), terephthalate (TPA), and byproduct bis(2‐hydroxyethyl) terephthalate (BHET). Subsequently, the second enzyme MHET hydrolase (IsMHETase) converts MHET into ethylene glycol and TPA. The end products can then be used in further applications such as making antifreeze and hybrid materials for plastic carrier bags, or simply be broken down by microorganisms into carbon dioxide and water. There are, however, concerns about the large‐scale application of microorganisms such as I. Sakaiensis for industrial recycling purposes, as the process is time consuming and often unreliable. Researchers have therefore begun looking at protein engineering as a means to allow enzymes like IsPETase and IsMHETase to be more efficient and degrade PET 100‐1000x faster. Some proposed solutions include narrowing the active‐site cleft, combining multiple PET‐active enzymes, and further lowering the protein’s optimal reaction temperature. The Ashbury College MSOE Center for BioMolecular Modeling A Protein Story (MAPS) team uses 3D modelling and printing technology to examine structure‐function relationships of the enzymes PETase and MHETase involved in the PET degradation process.