Expression and purification of an active cysteine protease of Haemonchus contortus using Caenorhabditis elegans

Many proteolytic enzymes of parasitic nematodes have been identified as possible targets of control. Testing these as vaccine or drug targets is often difficult due to the problems of expressing proteases in a correctly folded, active form in standard expression systems. In an effort to overcome these difficulties we have tested Caenorhabditis elegans as an expression system for a Haemonchus contortus cathepsin L cysteine protease, Hc-CPL-1. Recombinant Hc-CPL-1 with a polyhistidine tag added to the C-terminal was expressed in an active and glycosylated form in C. elegans. Optimal expression was obtained expressing Hc-cpl-1 under control of the promoter of the homologous C. elegans cpl-1 gene. The recombinant protein was purified from liquid cultures by nickel chelation chromatography in sufficient amounts for vaccination studies to be carried out. This study provides proof of principle that active, post-translationally modified parasitic nematode proteases can be expressed in C. elegans and this approach can be extended for expression of known protective antigens

Performance Appraisal Criteria and Innovative Work Behaviour: The Mediating Role of Employees’ Appraisal Satisfaction

Digitalization of work has recently rekindled the debate about the effectiveness of performance appraisal in encouraging innovative work behaviour. This study addresses this issue by hypothesizing that employees’ satisfaction towards their performance appraisal plays a mediating role in this relationship. Data collected from a sample of 865 Italian employees are used to estimate the mediation model. The main findings show that performance appraisal focused on the employees’ achieved results and new-developed competences boosts innovative behaviour more than traditional forms of evaluation based on time spent at the workplace, assigned tasks, working hours. Moreover, the employees’ satisfaction with the appraisal system and their performance rating agreement totally mediate the above relationship