NagZ modulates the virulence of E. cloacae by acting through the gene of unknown function, ECL_03795

• Published in: Virulence 2024-12, Vol.15 (1), p.2367652
• Main Authors: Yang, Xianggui, Zeng, Jun, Wang, Dan, Zhou, Qin, Yu, Xuejing, Wang, Zhenguo, Bai, Tingting, Luan, Guangxin, Xu, Ying
• Format: Article
• Language: English
• Subjects: Acetylglucosaminidase - genetics; Acetylglucosaminidase - metabolism; Animals; Bacterial Proteins - genetics; Bacterial Proteins - metabolism; c-di-GMP; Cyclic GMP - analogs & derivatives; Cyclic GMP - metabolism; E. cloacae; ECL_03795; Enterobacter cloacae - drug effects; Enterobacter cloacae - genetics; Enterobacter cloacae - pathogenicity; Enterobacteriaceae Infections - microbiology; Female; Gene Expression Regulation, Bacterial; Gene Knockout Techniques; Larva - microbiology; Mice; Moths - microbiology; NagZ; Virulence; Virulence Factors - genetics
• ISSN: 2150-5594; 2150-5608; 2150-5608
• DOI: 10.1080/21505594.2024.2367652

β-N-acetylglucosaminidase (NagZ), a cytosolic glucosaminidase, plays a pivotal role in peptidoglycan recycling. Previous research demonstrated that NagZ knockout significantly eradicated AmpC-dependent β-lactam resistance in . However, NagZ's role in the virulence of remains unclear. Our study, incorporating data on mouse and larval mortality rates, inflammation markers, and histopathological examinations, revealed a substantial reduction in the virulence of following NagZ knockout. Transcriptome sequencing uncovered differential gene expression between NagZ knockout and wild-type strains, particularly in nucleotide metabolism pathways. Further investigation demonstrated that NagZ deletion led to a significant increase in cyclic diguanosine monophosphate (c-di-GMP) levels. Additionally, transcriptome sequencing and RT-qPCR confirmed significant differences in the expression of ECL_03795, a gene with an unknown function but speculated to be involved in c-di-GMP metabolism due to its EAL domain known for phosphodiesterase activity. Interestingly, in ECL_03795 knockout strains, a notable reduction in the virulence was observed, and virulence was rescued upon complementation with ECL_03795. Consequently, our study suggests that NagZ's function on virulence is partially mediated through the ECL_03795→c-di-GMP pathway, providing insight into the development of novel therapies and strongly supporting the interest in creating highly efficient NagZ inhibitors.