Antimicrobial Resistance Genes, Mechanisms, and Next-Generation Antibiotics: A Review for the Effective Treatment of Multidrug-Resistant Pathogens

Marwah Ali Oudah; Nada Ahmed  Fairooz; Bushra Hamad  Obaid

doi:10.51699/cajmns.v7i2.3116

Authors

Marwah Ali Oudah AL-Furat AL-AwsatTechnical University, Al-Qadisiyah Polytechnic College, Iraq
Nada Ahmed Fairooz AL-Furat AL-AwsatTechnical University, Al-Qadisiyah Polytechnic College, Iraq
Bushra Hamad Obaid AL-Furat AL-AwsatTechnical University, Al-Qadisiyah Polytechnic College, Iraq

DOI:

https://doi.org/10.51699/cajmns.v7i2.3116

Keywords:

Antimicrobial Resistance, Multidrug-Resistant Pathogens, Resistance Genes, Next-Generation Antibiotics, Biofilm, Efflux Pumps

Abstract

Antimicrobial resistance (AMR) has become a growing global health concern due to the overuse and misuse of antibiotics in human medicine, agriculture, and animal care. This review aims to examine the major resistance genes, underlying mechanisms, and the potential of new-generation antibiotics in treating infections caused by multidrug-resistant (MDR) pathogens. A structured literature search was conducted using six databases—Scopus, Web of Science, PubMed, Google Scholar, ResearchGate, and Mendeley—focusing on studies published between 2015 and 2025. After applying inclusion criteria, 162 peer-reviewed articles were selected for analysis. These studies reported a wide range of resistance genes, with blaZ being the most common, found in approximately 64% of the reviewed literature. Other frequently mentioned genes included mecA (52%), erm (48%), tet (41%), and vanA/B (37%). Common MDR pathogens identified were Staphylococcus aureus (MRSA), Enterococcus (VRE), Enterobacteriaceae (CRE), and Pseudomonas aeruginosa. Resistance was found to occur through various mechanisms such as enzymatic degradation of antibiotics, altered binding targets, efflux pumps that remove antibiotics from bacterial cells, and the development of biofilms that reduce drug effectiveness. Several new treatment options—including cefiderocol, eravacycline, and silver/zinc-based nanoparticles—have shown encouraging results in overcoming resistance. Natural plant compounds and genomic-based drug discovery also offer promising directions. Overall, the findings highlight the urgent need for responsible antibiotic use, better diagnostic tools, and continued investment in alternative therapies. Without immediate action, AMR could make previously treatable infections far more dangerous and difficult to manage in the near future.

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