{'fraction_non_alphanumeric': 0.041015625, 'fraction_numerical': 0.0205078125, 'mean_word_length': 4.631868131868132, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
[Construction of an expression vector with elastin-like polypeptide tag to purify xylanase].

OBJECTIVE
This paper reports the purification of xylanase using the shortest, sensitive ELP [KV8F-20].


METHODS
We designed a thermophilic xylanase gene, and recombined it with the ELP via a random coil sequence to generate the vector pET-22b-SoxB-M2-S-ELP. The expressed xylanase was purified by inverse transition cycling through high-speed centrifugation, and then we characterized the purified xylanase.


RESULTS
The phase transition temperature of the ELPs dropped to 22 degrees C with 0.5 mol/L sodium carbonate (pH = 7). Under this condition, SoxB-M2-S-ELP was purified by 3.16 folds after centrifugation. The recovery rate was 21.2%, and purity of the xylanase was 64.3%.


CONCLUSION
Elastin-like polypeptide as a purification tag to purify recombinant proteins is simple, fast, gentle and cheaper. The expression vector we constructed here might be a very useful and reliable tool to purify many other target proteins.