economics Nature Is Weird

A common vitamin can act as a shield that makes superbugs immune to 'last-resort' antibiotics.

April 14, 2026

Original Paper

Nutrient-Driven Small-Colony Variants as an Adaptive Outcome in Carbapenem-Resistant Acinetobacter baumannii

Samyar Moheb, Shayra D. Sanchez, Irene Luu, Azadeh Varnado, German M. Traglia, Karina Lopez, Jenny Escalante, Cecilia Rodriguez, Marisel R. Tuttobene, Marcelo Tolmasky, Robert A. Bonomo, Luis A. Actis, Gauri Rao, Fernando Pasteran, Maria Ramirez

SSRN · 6571421

The Takeaway

Vitamin B12 tells bacteria to hunker down into a dormant, slow-growing state. In this state, the strongest antibiotics in a doctor's arsenal become useless, allowing the bacteria to survive the very drugs designed to kill them.

From the abstract

Carbapenem-resistant Acinetobacter baumannii (CRAB) is a serious threat, and resistance to the last-resort drug cefiderocol is emerging. However, how host micronutrients drive persistence-like adaptation is poorly defined. Using the AB5075 and CDC AR Bank #0033 (M27835) CRAB isolates, we combined time-kill assays, whole-genome sequencing, gene expression analysis, and phenotyping to test how vitamin B12 promotes small-colony variants (SCVs) and alters cefiderocol response. Vitamin B12 reproducib