Effect of Bacterial Infection on the Edibility of Aquatic Products: The Case of Crayfish (Procambarus clarkii) Infected With Citrobacter freundii

Abstract

Aquatic products are one of the world’s essential protein sources whose quality and safety are threatened by bacterial diseases. This study investigated the possible effects of bacterial infection on the main edible part, the muscle, in the case of crayfish infected with Citrobacter freundii. The histopathological analysis confirmed that crayfish was sensitive to C. freundii and muscle was one of the target organs. The transcriptome results showed impaired intercellular junctions, downregulation of actin expression, and inhibition of metabolic pathways. Furthermore, transcriptomic results suggest that C. freundii mainly affect muscle structure and nutrition. Subsequent validation experiments confirmed structural damage and nutrient loss in C. freundii infected crayfish muscle. Besides, the spoilage tests showed that C. freundii did not accelerate muscle spoilage and the bacteria had a limited impact on food safety. Therefore, although C. freundii may not be a specific spoilage bacterium, it still affects the edible taste and nutritional value of crayfish muscle. The findings of this study might contribute to further research on C. freundii infection and provide a warning about the adverse effects of bacterial infection on aquatic products.

Antimicrobial-Resistant Bacteria from Free-Living Green Turtles (Chelonia mydas)

“…Citrobacter is an opportunistic pathogen in some animals that causes severe aquaculture issues, leading to fish mortality. Findings of Citrobacter resistance in a neck sample suggest environmental contamination [ 34 , 35 ]. Gentamycin revealed resistance in C. cellulans , C. freundii , and Microbacterium spp.…”

Understanding the Role of Filamentous Actin in Food Quality: From Structure to Application

“…(b) Muscle bundles were dissolved and necrotic and formed part of the cavity (red pentagram). Reprinted from ref . (D) The illustration of degraded and oxidized myofibrillar protein in brined bighead carp fillet after frozen storage.…”

“…It is also the main direct target of bacteria to destroy the structure of cell actin and reduce the phagocytosis activity of host cells. For instance, Clostridium botulinum depolymerizes actin, the bacterial effector produced by Yersinia enterocolitica binds to G-actin and is activated to disrupt the destruction of F-actin and impair host phagocytosis, Citrobacter freundii can downregulate the expression of actin, destroying the structural integrity of muscle (Figure C), the effector protein hemagglutinin protease of Aeromonas salmonicida has significant protein hydrolytic activity, and its active site binds to MPs through hydrophobic interactions and hydrogen bonds to cleave peptide bonds between Gly44-Val45 in actin and Ala825-Phe826 in the myosin heavy chain . The proteases derived from Penicillium aethiopicum and Penicillium chrysogenum have been characterized as alkaline serine proteases and serine protease, respectively.…”