# Defining microbial and host determinants of Acinetobacter survival in the urinary tract

> **NIH NIH K08** · UNIVERSITY OF ALABAMA AT BIRMINGHAM · 2022 · $143,729

## Abstract

Project Summary and Abstract
 Up to 20% of all Acinetobacter baumannii (Ab) clinical isolates are obtained from urinary sources, and a
large portion of these urinary cases have their onset outside of hospitals. 40-60% of urinary isolates in our region
are multidrug resistant (MDR), demonstrating how Ab contributes to the growing epidemic of multidrug resistant
(MDR) urinary tract infections (UTIs). Despite the demand for novel, antibiotic-sparing interventions against Ab
UTIs, the microbial factors that mediate uropathogenic A. baumannii (UPAb) virulence and the host factors that
predispose to UPAb infections, remain poorly defined. We recently demonstrated that Ab strains vary in their
ability to colonize the urinary tract in a murine UTI model. Additionally, we identified microbial elements that
increase an Ab strain’s ability to infect bladders but do not contribute to its virulence in respiratory infections.
Lastly, in a recent epidemiological study, we found that Ab urinary and respiratory cases exhibited diverging
clinical and microbiological characteristics. Altogether, these findings are strongly suggestive that UPAb
comprise an Ab subpopulation distinctively equipped to infect urinary tracts, compared to Ab that cause other
types of infections.
 This proposal addresses fundamental points in understanding Ab epidemiology and pathobiology, with a
specific focus on Ab urovirulence:
 1) Are UPAb a distinguishable subpopulation of clinically-relevant Ab?
 2) Do host predisposing factors differ between Ab UTI versus other types of Ab infections? Versus
 UTI caused by other, more common uropathogens (i.e., Enterobacteriaceae or Pseudomonas)?
 3) Can reducing UPAb’s intrinsic ability to survive in urine be a strategy to curb its urovirulence?
 Using comparative genomic analysis pipelines developed in the Dantas Lab, I will investigate microbial
molecular determinants of urinary disease in a large bank of Acinetobacter clinical isolates matched to their
respective clinical data. I will also identify host characteristics associated with Ab UTI in a published retrospective
cohort of over 2000 Ab cases in our healthcare system. Lastly, employing molecular techniques and murine UTI
models developed in the Feldman lab, I will investigate the prospective link between a UPAb strain’s ability to
grow in human urine, and its ability to infect the murine urinary tract. This will evaluate whether in vitro urine
growth models can be effectively employed to screen for MDR Ab UTI therapeutic targets. Through successful
completion of this research, undergoing the didactic training, and receiving guidance from a multidisciplinary
mentoring committee of experts, I aim to launch my career as an independent translational researcher
investigating the host and microbial determinants of pathogenesis in neglected forms of Acinetobacter disease.

## Key facts

- **NIH application ID:** 10436811
- **Project number:** 5K08AI148582-04
- **Recipient organization:** UNIVERSITY OF ALABAMA AT BIRMINGHAM
- **Principal Investigator:** Juan Jose Calix
- **Activity code:** K08 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2022
- **Award amount:** $143,729
- **Award type:** 5
- **Project period:** 2020-07-01 → 2025-06-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10436811

## Citation

> US National Institutes of Health, RePORTER application 10436811, Defining microbial and host determinants of Acinetobacter survival in the urinary tract (5K08AI148582-04). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10436811. Licensed CC0.

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