Pathogenic bacterial toxins and virulence influences in cultivable fish

Abstract

Bacterial virulence factors play a major role in infection, which provides devastating effect on the aquaculture industry. Bacterial toxins are the major virulence factors that influence the roles of host cells and take control of living organisms’ vital processes to facilitate microbial infection. Various other bacterial virulent components such as adhesins, capsular polysaccharides, lipopolysaccharides, bacterial flagellum, pili and microbial siderophore provide a diverse effect in the microbial pathogenesis and express a variety of pathogenic molecules including aebABCEG, HutA, cpsD and pPHDD1. Bacterial protein secretion system secretes enzymes and toxins from bacterial cytoplasm to the host membrane targeting the immune cells and promoting biofilm formation. However, as they enter, the host body expresses various immune molecules that interact to utilize the pathogen recognition receptors. Toxins are powerful molecules formed by a broad range of bacterial pathogens attacking host cells and playing key roles in the dialogue between host and pathogen. They are important virulence factors that are often enough to decide the outcome of the infection. Hence, a detailed view on the virulence molecules majorly exotoxins from various bacterial pathogenic strains that are necessary to understand the pathogenesis. This review focuses on bacterial toxins and various other virulence factors, which influence the pathogenesis in fish.

Isolation and Characterization of Vibrio kanaloae as a Major Pathogen Associated with Mass Mortalities of Ark Clam, Scapharca broughtonii, in Cold Season

“…The iron uptake process of bacterial pathogens was often associated with their pathogenic process [ 42 , 72 , 73 ]. Hemolysin and siderophore are critical virulence factors for bacterial pathogen colonization and the establishment of infection [ 33 , 42 , 74 , 75 ]. The temperature-regulated production of hemolysin and siderophore has been identified in several bacterial genera.…”

The pan‐genome of Splendidus clade species in the familyVibrionaceae: Insights into evolution, adaptation, and pathogenicity

“…Secretion systems (SSs) in bacterial pathogens are responsible for the secretion of various proteins and toxins which contribute towards promoting bacterial virulence, six different SSs have been identified in Gram‐negative bacteria, type I secretion system (T1SS) to Type VI system (T6SS) (Sarkar et al, 2021; Zhang & Li, 2021). Many pathogens use dedicated SSs to secrete proteins involved in virulence from the cytosol of the bacteria into host cells or the host environment, but T3SS and T5SS were found to be less associated with virulence (Green & Mecsas, 2016).…”

“…Bacterial toxins are the major virulence factors that affect the functions of host cells and control the vital processes of living organisms so they can facilitate microbial infection, they are one of the most important virulence factors that determine whether an infection will succeed or fail (Sarkar et al, 2021). The hemolysin toxins Vah and MARTX have been characterized as mainly responsible for the hemolytic and cytotoxic activity of fish pathogens, which cause erythrocyte lysis in the host cells (Frans et al, 2011).…”

Synergies in antimicrobial treatment by a levofloxacin-loaded halloysite and gold nanoparticles with a conjugation to a cell-penetrating peptide

“…42 The secreted enzymes by the bacteria are responsible for the created resistance. 43–45 Therefore, layer-by-layer encapsulation of antibiotic drug molecules into the carrier system can be a substantial strategy for disconnecting the drug molecules from targeted bacterial cells and subsequent safety of the subjected drug. This particular advantage makes HNTs a suitable vehicle for drug delivery purposes.…”