Liang Wang

By Liang Wang and Bing Gu

Part of the book: Recent Advances in Bacterial Biofilm Studies

By Muhammad Usman, Huan Yang, Jun-Jiao Wang, Jia-Wei Tang, Li-Yan Zhang and Liang Wang

Microbial biofilms are complicated structures in which planktonic cells change to a sessile form of growth. The development of an extracellular polymeric substance (EPS) matrix, which encloses the bacterial cells and offers additional protection, supports that kind of growth. Biofilms present a significant threat to public health due to their extreme resistance to higher antibiotic concentrations. In addition, biofilms are also resistant to human immune systems. Bacterial biofilms can spread their pathogenicity through a variety of approaches, such as adhering to a solid surface, evading host defenses like phagocytosis, generating a large amount of toxins, resisting anti-microbial agents, transferring genes to generate more virulent strains, and dispersing microbial aggregates that transport the microorganisms to new locations. Consequently, there is an urgent need to replace the widespread procedure of antibiotics with novel developing approaches. Furthermore, biofilm formation has been connected with high rates of disease, health-related infections, and even death, leading to the search for alternative treatment approaches. The review intends to provide information about clinically important bacterial pathogens of the gut, mouth, skin, and lungs and insights into the different perceptions of microbial biofilms, as well as their formation, regulation, and pathogenicity. In addition, for efficient eradication or inhibition of biofilms and associated infections, nanoparticle approaches for addressing persistent bacterial infections have also been discussed.

Part of the book: Recent Advances in Bacterial Biofilm Studies

By Yi-Wen Liao, Yu-Rong Qin and Liang Wang

Drug-resistant tuberculosis (TB) and non-tuberculous mycobacteria (NTM) infections pose significant global health challenges. Understanding the genomic diversity, pathogenicity, and mechanisms of antibiotic resistance in Mycobacterium species is critical for developing effective diagnostic tools and therapeutic strategies. This study conducted a comparative analysis of 632 Mycobacterium genomes obtained from the public database Bacterial and Viral Bioinformatics Resource Center (BV-BRC). The analysis focused on Mycobacterium tuberculosis (Mtb) and NTM. Techniques included comparative genome analysis, multilocus sequence typing (MLST), and phylogenetic analysis to identify sequence types (STs) and characterize virulence factors and antibiotic resistance genes. The study identified significant sequence types, with ST21 and ST27 being the most prevalent, associated with high transmission potential, virulence, and multidrug resistance. Analysis of virulence factors highlighted the essential roles of ESX-1, ESX-3, and ESX-5 secretion systems in host immune evasion and nutrient acquisition. Antibiotic resistance profiles revealed the widespread presence of resistance genes, including those conferring resistance to aminoglycosides (e.g., AAC(2′)-Ic) and macrolides (e.g., Erm(37)). Efflux pump genes such as efpA and mtrA were prevalent, contributing significantly to multidrug resistance. These findings give insights into the genomic diversity and molecular mechanisms driving pathogenicity and drug resistance in Mycobacterium species. The results identify key targets for the development of innovative diagnostic tools and therapeutic interventions, advancing efforts to combat drug-resistant TB and NTM infections. Furthermore, this research underscores the importance of genomic surveillance in informing public health strategies to mitigate the spread of drug-resistant Mycobacterium strains.

Part of the book: Diagnosis and Treatment of Mycobacterial Infections