Abstract
Inorganic pyrophosphatase (PPase) participates in energy cycle and plays a vital role in hydrolysis of inorganic pyrophosphate (PPi) into inorganic phosphate (Pi). The aim of this study was to investigate the biological properties of a Trichinella spiralis PPase (TsPPase) and its role in larval molting and developmental process. The predicted TsPPase consisted of 367 amino acids with a molecular mass of 41.48 kDa and a pI of 5.76. Amino acid sequence alignment and phylogenetic analysis showed that the TsPPase gene encodes a functional family I soluble PPase with the same characteristics as prokaryotic, plant and animal/fungal soluble PPase. The rTsPPase was expressed and purified, it has the activity to catalyze the hydrolysis of PPi to Pi, and the activity was dependent on Mg2+, pH and temperature. The enzymatic activity of rTsPPase was significantly inhibited after its metal binding sites mutation. TsPPase was transcribed and expressed in all T. spiralis phases, especially in muscle larvae (ML) and intestinal infective larvae (IIL). Immunofluorescence assay (IFA) revealed that TsPPase was mainly located in cuticle and stichosome. When the ML and IIL were treated with TsPPase-specific siRNA-279, TsPPase expression and enzymatic activity were obviously reduced, the larval molting and development were also impeded. Intestinal IIL as well as AW burden, IIL molting rates from mice infected with siRNA-treated ML were obviously suppressed. The results indicated that rTsPPase possesses the enzymatic activity of native inorganic pyrophosphatase, and TsPPase plays an important role in development and molting process of intestinal T. spiralis larval stages.
Highlights
Trichinellosis is mainly caused by the infection of Trichinella spiralis which is a zoonotic tissue-dwelling nematode infecting over 150 kinds of mammals around the world [1]
In the process of the reaction, PPase can catalyze the hydrolysis of substrate inorganic pyrophosphate (PPi) into two molecules of phosphate (Pi), controlling the concentration of pyrophosphate in cells and regulating the intracellular water-salt balance
Previous studies indicated that inorganic pyrophosphatase (PPase) played an important role in parasite survival in the host, such as in the life cycle of Plasmodium and Toxoplasma gondii, PPase played an important role in the regulation of growth and cell division [66]
Summary
Trichinellosis is mainly caused by the infection of Trichinella spiralis which is a zoonotic tissue-dwelling nematode infecting over 150 kinds of mammals around the world [1]. After the infected meat is ingested, infectious T. spiralis muscle larvae (ML) are released in the stomach from the capsules under the digestion of gastric fluid and develop into intestinal infective larvae (IIL) [12, 13]. Inorganic pyrophosphatases (PPases) play a crucial role in energy cycle and the hydrolysis of inorganic pyrophosphate (PPi) into inorganic phosphate (Pi) [20]. This is an exergonic reaction and can be coupled to several unfavorable and energy demanding biochemical transformations such as DNA replication, protein synthesis and lipid metabolism [21]. I contains most of the known soluble PPases, and can be divided into four categories (prokaryotes, fungi, animals and plants) according to their sequence and interspecific distribution. All PPases need the participation of Mg2+ for enzyme activity [27]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
