Jing Fang is a PhD student at Ocean College of Qinzhou University, Qinzhou, China

Reoviruses are widespread and infect a broad range of hosts. To date, no study has been reported on an aquatic reovirus receptor. By using viral overlay protein binding assay (VOPBA), swimming crab Portunus trituberculatus reovirus (SCRV) was found to bind to a protein of approximately 550 kDa. MALDI-TOF MS–MS analysis revealed that the protein shares the closest homology with β-tubulin. Mouse membrane proteins were tested by western blot with antibodies against the SCRV-binding protein and mouse tubulin, and uniform positive bands were obtained. The results indicated that the SCRV-binding protein was tubulin. The interaction between tubulin and SCRV was further confirmed with co-immunoprecipitation. SCRV infection in vitro could be blocked by a tubulin-specific antibody. The role of tubulin as a major cell surface protein has been reported previously. These findings suggest that tubulin mediates SCRV infection and may function as a receptor for SCRV.

Thu Diem Nguyen has completed her PhD from University of Tasmania, Australia. She is a Researcher at Research Institute for Aquaculture No. 2, Vietnam. Her research interests focus on various aspects of “Fish health, such as fish bacteriology, fish vaccination, fish immunology and fish pathology”.

Acute hepatopancreatic necrosis disease (AHPND) caused by Vibrio parahaemolyticus has resulted in significant economic losses in shrimp production in Vietnam. Previous studies reported that V. parahaemolyticus showed multiple-antibiotic resistance due to the misuse of antibiotics to control pathogenic infections in aquaculture. There is a lack of information on the use of antibiotics by shrimp farmers and the knowledge regarding the presence of V. parahaemolyticus in the Mekong Delta, Vietnam. This study aimed to investigate the incidence of pathogenic Vibrio parahaemolyticus and assess the antibiotic resistance profile as well as to perform the antimicrobial susceptibility test in V. parahaemolyticus isolates in the Mekong Delta, Vietnam. The study was carried out through a survey on the use of antibiotics in 76 grow-out shrimp farms and identification of the occurrence of AHPND pathogenic V. parahaemolyticus isolates in a total of 396 shrimp, water and mud samples collected in the Mekong Delta, Vietnam. 47 AHPND pathogenic V. parahaemolyticus isolates were tested for sensitivity to 13 antibiotics. The results showed that the presence of AHPND pathogenic V. parahaemolyticus isolates was 12.37% in the total of 396 samples. Oxytetracycline, doxycycline and enrofloxacin were the most common antibiotics used in shrimp farms. The study showed high percentage of amoxicillin and ampicillin resistance (80.85% and 78.72%, respectively) by AHPND pathogenic V. parahaemolyticus isolates, suggesting these two antibiotics should be excluded in the treatment of V. parahaemolyticus.