New Class of Encrypted Peptides Offer Hope in Fight Against Antibiotic Resistance

by Eric Horvath

Cesar de la Fuente, Presidential Assistant Professor with appointments in the Perelman School of Medicine, School of Engineering and School of Arts & Sciences (Image: Eric Sucar)

In a significant advance against the growing threat of antibiotic-resistant bacteria, researchers have identified a novel class of antimicrobial agents known as encrypted peptides, which may expand the immune system’s arsenal of tools to fight infection. The findings, published in Trends in Biotechnology by Cell Press, reveal that many antimicrobial molecules originate from proteins not traditionally associated with immune responses.

Unlike conventional antibiotics that target specific bacterial processes, these newly discovered peptides disrupt the protective membranes surrounding bacterial cells. By inserting themselves into these membranes—much like breaching a fortress wall—the peptides destabilize and ultimately destroy the bacteria.

“Our findings suggest that these previously overlooked molecules could be key players in the immune system’s response to infection,” says César de la Fuente, presidential assistant professor in bioengineering and in chemical and biomolecular engineering in the School of Engineering and Applied Science, in psychiatry and microbiology in the Perelman School of Medicine, and in chemistry in the School of Arts & Sciences, who led the research team. “This may not only redefine how we understand immunity but also opens up new possibilities for treating drug-resistant infections.”

Read the full story in Penn Medicine News.

Developing Kidneys from Scratch: Alex Hughes Tackles the Tremendous Burden of Kidney Disease

by Ian Scheffler

Alex Hughes, Assistant Professor in Bioengineering, holds a model of a developing kidney. (Credit: Bella Ciervo)

To Alex Hughes, Assistant Professor in Bioengineering within Penn Engineering and in Cell and Developmental Biology within Penn Medicine, the kidney is a work of art. “I find the development of the kidney to be a really beautiful process,” says Hughes.

Most people only ever see the organ in cross-section, through textbooks or by dissecting animal kidneys in high school biology class: a bean-shaped slice with lots of tiny tubes. “I think that really undersells how amazing the structure is,” says Hughes, who points out that kidneys grow in utero like forests of pipes, branching exponentially.

Densely packed with tubules clustered in units known as nephrons, kidneys cleanse the blood, maintaining the body’s fluid and electrolyte balance, while also regulating blood pressure. The organ played a crucial role in vertebrates emerging from the ocean: as one paper puts it, kidneys preserve the primordial ocean in all of us.

Unfortunately, kidneys struggle in the modern world. Excessively salty food, being overweight, not exercising enough, drinking too much and smoking can all raise blood pressure, which damages the kidney’s tiny blood vessels, as does diabetes.

In some cases, damage to the kidney’s nephrons can be slowed with lifestyle changes, but, unlike the liver, bones and skin, which can regrow damaged tissue, kidneys have a limited capacity to regenerate. At present, without a transplant, the nephrons we have at birth must last a lifetime.

Read the full story in Penn Engineering Today.