Expression and characterization of digestive enzyme genes from hepatopancreatic transcripts from redclaw crayfish (Cherax quadricarinatus)

Abstract

Redclaw crayfish, Cherax quadricarinatus, possess a number of biological and commercial attributes that make them ideal for commercial aquaculture. While some studies have investigated digestive enzyme activity and nutritional requirements of this species, little information exists about the expression of digestive enzyme genes and their role in regulating digestive capacity. The current study therefore sequenced and annotated a RNASeq library constructed from a redclaw hepatopancreas to identify genes involved in digestive enzyme production. We observed that most of the transcripts that were annotated as digestive enzyme genes are associated with carbohydrate metabolism, thus confirming that redclaw have an innate capacity to digest a range of carbohydrate substrates. While endoglucanases were the most abundant group of digestive enzymes found, a number of novel transcripts were also detected. Here, we provide the first report for the presence and expression of endo-b-mannanase in freshwater crayfish. This novel gene showed significant alignment with a GH5 family protein from marine Limnoriids, wood borers that do not possess symbiotic microbes in their gut system. Overall, the data generated here provide an important resource to better understand the suite of digestive enzymes in redclaw that are very useful to fully utilize the species' digestive capacity and will assist development of specific artificial feeds.

Prospection of putative genes for digestive enzymes based on functional genome of the hepatopancreas of Amazon river prawn

“…Yet, a search in the NCBI database revealed that this was the first time that an endo-betamannanase has been reported for the genus Macrobrachium. The enzyme amino acids sequences presented in M. amazonicum have high similarities with two registered species of endogenous mannanase production: Limnoria quadripunctata isopode 81% (King et al, 2010) and Cherax quadricarinatus decapode, 79% (Dammannagoda et al, 2015), and were classified as GH5 family constituent. The enzyme found in the present study was classified as key component for the degradation of structural polysaccharides (mannane) found in plant hemicellulose (Handford et al, 2003).…”

“…The utilization of Next Generation sequencing -NGS system enabled the massive sequencing of genes (functional genome), further improving the knowledge in this area. Nine putative functional sequences have been described in C. quadricarinatus (Dammannagoda, Pavasovic, Prentis, Hurwood, & Mather, 2015). This approach has also been used to characterize cellulose-digesting enzymes in M. rosenbergii (Ong et al, 2016) and to provide the transcriptome of M. nipponense under environmental hypoxia (Sun et al, 2014).…”

Tasa de depredación de Panulirus argus (Decapoda: Palinuridae) sobre moluscos gastrópodos en dos zonas pesqueras al sur de Cuba

“…Aunque para P. argus se ha demostrado in vitro que la digestión de carbohidratos que provienen de la materia vegetal, como alginato, agar y celulosa, poseen baja hidrólisis (Casuso et al 2014), en algunas langostas de agua dulce, como Cherax quadricarinatus (Xue et al 1999, Dammannagoda et al 2015, Cherax destructor y Euastacus sp. (Linton et al 2006), se han reportado genes que codifican la expresión de enzimas capaces de digerir la celulosa.…”

Presence and activity of endo-β-1,4-mannase, an important digestive carbohydrase within the digestive fluid of terrestrial crustaceans

“…A similar GH5_10 endo-β-1,4-mannase was also expressed in the crayfish Cherax quadricarinatus (Dammannagoda et al 2015;Tan et al 2016). In this species, and in contrast to G. natalis, four transcripts are expressed with their level of expression being lower than that of endo-β-1,4-glucanase (Dammannagoda et al 2015;Tan et al 2016). The putative amino acid sequence of the GH5_10 transcript from G. natalis contained a hydrophobic signal peptide which suggests that it is an extracellular enzyme (Gan et al 2018).…”

“…The enzyme was present as a single transcript and had the highest level of expression out of all of the carbohydrases; this included a GH13_24 amylase, a GH9 endo-β-1,4-glucanase and a GH16 β-1,3-glucanase (Gan et al 2018). A similar GH5_10 endo-β-1,4-mannase was also expressed in the crayfish Cherax quadricarinatus (Dammannagoda et al 2015;Tan et al 2016). In this species, and in contrast to G. natalis, four transcripts are expressed with their level of expression being lower than that of endo-β-1,4-glucanase (Dammannagoda et al 2015;Tan et al 2016).…”