Molecular isolation and characterization of a haemocyanin ofMacrobrachium rosenbergiireveal its antibacterial activities

Abstract

Haemocyanin is a multi-subunit protein complex found in the haemolymph and is involved in the immune system of crustaceans. In this study, a haemocyanin gene of

Molecular isolation and expression analysis of hemocyanin isoform 2 of Macrobrachium rosenbergii

“…Phylogenetic analysis revealed that Mr Hc2 is closely related to Hc‐1 of M. nipponense (92.49% identity; Kong et al 2016). However, Mr Hc2 exhibited only 61.55% identity with Mr Hc from M. rosenbergii in our previous study (Srisuk et al 2018). This evidence demonstrates the diversity of hemocyanin functions that descend from evolutionarily derived sequence variance.…”

“…In the present study, Mr Hc2 protein with a molecular mass of 77.3 kDa might correspond to the 78‐kDa subunit of Mr Hc4. The Mr Hc protein in our previous study, which had a molecular mass of 76.5 kDa, might correspond to the 76‐kDa subunit of Mr Hc4 (Srisuk et al 2018).…”

“…This conserved domain is a highly variable genetic sequence that is structurally homologous to Ig, which exerts a response to bacteria based on different mechanisms, including glycosylation modification (Zhang et al 2017). In our previous study, the Ig‐like domain of Mr Hc exhibited antibacterial activity against the gram‐positive bacterium B. cereus and various shrimp pathogenic gram‐negative bacteria, including V. parahaemolyticus , V. vulnificus , A. caviae , A. hydrophila , and A. veronii (Srisuk et al 2018). In the case of Mr Hc2, the recombinant Ig‐like domain protein did not show antibacterial activity (data not shown).…”

“…In our previous study, the hemocyanin content of M. rosenbergii ( Mr Hc) was significantly increased after challenge with M. rosenbergii nodavirus ( Mr NV). Hemocyanin isoform 2 ( Mr Hc2) in M. rosenbergii exhibits antibacterial activity against V. parahaemolyticus , V. vulnificus , Aeromonas caviae , A. hydrophila , A. veronii , and Bacillus cereus (Srisuk et al 2018).…”

“…Hemocyanin is a multifunctional protein involved in nonspecific immune activity (Destoumieux‐Garzon et al 2001; Zhang et al 2004; Srisuk et al 2018). In the case of antibacterial activity, the affinity proteomic strategy was utilized to identify hemocyanin of L. vannamei , which showed agglutination activity with various gram‐negative bacteria, including Vibrio spp.…”