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Noncoding small RNAs are essential for modulating bacterial gene expression, especially under carbon and nutrient-limited conditions. In this study, by employing both in silico and molecular hybridization tools, we identified a carbon source responsive small RNA in A. baumannii DS002. Expression of corresponding gene, abcR200, located at the intergenic region of omt (O-methyltransferase) and orf72 genes, is under the transcriptional control of a global transcriptional factor, Leucine Responsive Regulatory Protein (Lrp). A sequence motif that serves as a target for Lrp was found overlapping the abcR200 promoter (P abcR200 ). Chromatin immunoprecipitation (ChIP) demonstrated that Lrp oligomers, formed under low leucine conditions, strongly interacted to the P abcR200 . However, the observed interactions were disrupted in the presence of leucine, as leucine promoted dissociation of Lrp to monomers and dimers, the conformation unfavourable to interact with P abcR200. The abcR200 promoter activity increased with increase of exogenous leucine concentrations, and at 2 mM maximum promoter activity was observed. The AbcR200 target mRNAs were identified by analysing the transcriptome of abcR200 negative strain of A. baumannii. Intriguingly, in abcR200 negative background, expression of lut (lactate utilization) mRNA has increased, suggesting that lut mRNA as one of the mRNA targets for AbcR200. Consistent of this observation, there existed extensive sequence complementarity between AbcR200 and lut mRNA, especially in the regions coding LutP, LutE and LutR. In support of the observed sequence complementarity, the levels of lut mRNA encoded proteins got elevated in abcR200 negative HS002 strains suggesting a role for AbcR200 in translational inhibition of lut mRNA., Competing Interests: Conflict of Interest Statement The authors of this paper declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported herein. This encompasses any financial arrangements, affiliations, or involvements with organizations that may have influenced the research process, analysis, or interpretation of results. Additionally, the authors affirm that they have not received any financial support or other benefits from entities with an interest in the subject matter discussed in this paper., (Copyright © 2025 The Authors. Published by Elsevier Inc. All rights reserved.)