Graduate Student Spotlight

Anna Johnston


Anna Johnston is a graduate student at UC Santa Cruz in the Chemistry and Biochemistry doctorate program. She is a member of Alexander Ayzner’s lab which takes its inspiration from the process of photosynthesis and strives to design a green route to inexpensive, soft materials for light-harvesting. Her research involves conjugated polyelectrolytes (CPEs), water-soluble polymer semiconductors that absorb visible light, and the study of their mechanical and photophysical properties for materials applications. Polyelectrolyte complexes have been shown to exhibit liquid-liquid phase separation, termed coacervation, in which the polyelectrolytes self-assemble and partition into a dilute and concentrated phase. This phenomenon has raised interest in using these systems as membraneless organelle mimics, where the concentration of polyelectrolytes is analogous to the crowding of biological components which is believed to have contributed to early cell development. Anna is specifically interested in studying coacervation in CPE complexes, composed of an oppositely charged (energy donor/acceptor) CPE pair, and exploiting the optical properties of these materials as a step toward designing artificial light-harvesting organelles.

Anna is involved in outreach with the UCSC group Women in Science and Engineering (WISE) in which she helps expose middle school girls to different STEM disciplines through on campus lab tours and hands-on activities. She is also the 2019/20 Center for Innovative Teaching and Learning (CITL) fellow for the Chemistry Department, a role which allows her to work with the department in enhancing pedagogy through TA training. In the future, Anna plans to advance her field as a professor. She hopes to encourage future generations to pursue STEM fields, and to enhance the public’s relationship to science through education.


 Jocelyn Macho 


I am a graduate student at UC Santa Cruz in the Chemistry doctoral program. The aims of my research project are centered around exploiting NP-34, a novel, boron-containing natural product isolated from marine Streptomyces (an Actinobacteria which is used as source for antibiotics for humans), to both discover the target receptors in mosquitos of toxins and to pinpoint the most potent, mosquito-selective analog to employ in “greener” pesticides. This natural product exhibited selective toxicity to mosquito cells. Preliminary data demonstrated an 80% kill rate at 50 nm against mosquito cells and selective over moth, fly, and human cells. Thus, using click chemistry, we plan to expose mosquito-specific vulnerabilities. We are also in the process of both isolating and synthesizing various analogs of NP-34 for structure-activity relationship studies to determine maximum efficacy of our compound.

I decided to go to graduate school as I have always had the desire to teach, and since high school I have known that I wanted to be a professor. Being a first-generation college student and also a Hispanic student, I wanted to serve as an inspiration for younger students, to show that you are not bound by the modifiers “first-generation” or “minority.” I have also always wanted to make an impact in human health. My mother is diabetic and disabled, and watching her struggles throughout my entire life inspired my efforts to make an impact in the health community. I decided that through research in the biomedical realm I could help shape the medical world through pharmaceuticals. I chose UC Santa Cruz so that I could work for Dr. John MacMillan, whose work focuses on exploiting the biological activities of marine-derived natural products. With my work in graduate school I believe that in the future I will impact the field of natural products and help develop target-selective and effective medications, using not only my own work in the laboratory, but also by being a teacher and mentor for future scientists to do the same.