Formation and hydrolysis of amide bonds by lipase A from Candida antarctica; exceptional features

2010 ◽  
Vol 8 (4) ◽  
pp. 886 ◽  
Author(s):  
Arto Liljeblad ◽  
Pauli Kallio ◽  
Marita Vainio ◽  
Jarmo Niemi ◽  
Liisa T. Kanerva
2012 ◽  
Vol 66 (2) ◽  
pp. 201-206
Author(s):  
Aleksandra Dimitrijevic ◽  
Dusan Velickovic ◽  
Ratko Jankov ◽  
Nenad Milosavic

Yeast Candida antarctica produces two lipase forms, which are widely used as catalysts in variety of organic reactions, many of which are applied on a large scale. In this work, production of two forms of lipase from C. antarctica DSM 70725 (CAL A and CAL B) was monitored during seven days of cultivation in the optimal medium using different electrophoretic and zymographic techniques. According to electrophoresis after silver staining, C. antarctica lipase A (molecular mass 45 kDa) was produced starting from the second day of cultivation. C. antarctica lipase B (CAL B) was also produced starting from the second day, but protein was present in the fermentation broth predominantly as dimer (molecular weight 66 kDa), while presence of monomeric form of CAL B (molecular weight of 33 kDa) was observed starting from the fourth day of cultivation. Both types of zymograms (based on hydrolysis and synthesis reactions) were used for detection of lipase activity in the fermentation broth. C. antarctica lipase A showed activity only in hydrolytic zymogram, when ?-naphtyl butyrate was used as substrate. In the same zymogram, with ?-naphtyl acetate as substrate no CAL A activity was detected. Similarly, CAL A showed no activity in synthesis based zymograms towards oleic acid and octanol as substrates, indicating that CAL A is not active towards very short or long-chain substrates. As opposite of CAL A, both monomeric and dimeric form of CAL B were detected in the all zymograms, suggesting that CAL B is active towards wide range of substrates, regardless to the chain length. Thus, zymogram based on hydrolysis of ?-naphtyl butyrate represents a simple method for monitoring the production of two forms of lipase from C. antarctica, that greatly differ in their characteristics.


Water ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1645 ◽  
Author(s):  
Byung-Moon Jun ◽  
Yeomin Yoon ◽  
Chang Min Park

This research focused on the influence of post-treatment using alkali-catalyzed hydrolysis with a full-aromatic nanofiltration (NF) polyamide membrane and its application to the efficient removal of selected dyes. The post-treated membranes were characterized through Fourier transform infrared spectroscopy, goniometry, and zeta-potential analysis to analyze the treatment-induced changes in the intrinsic properties of the membrane. Furthermore, the changes in permeability induced by the post-treatment were evaluated via the measurement of water flux, NaCl rejection, and molecular weight cutoff (MWCO) under different pH conditions and post-treatment times. Major changes induced by the post-treatment in terms of physicochemical properties were the enhancement of permeability, hydrophilicity, and negative charge due to the hydrolysis of the membrane’s amide bonds. Four different dyes were selected as representative organic pollutants considering the MWCO of the post-treated membranes. Compared with the pristine NF membrane, membranes post-treated at pH 13.5 showed better water flux with similar rejection of the target dyes. On the basis of these results, the proposed post-treatment method for NF membranes can be applied to the removal of organic pollutants of various size.


ChemBioChem ◽  
2019 ◽  
Vol 20 (11) ◽  
pp. 1438-1443 ◽  
Author(s):  
Johanna Löfgren ◽  
Tamás Görbe ◽  
Michael Oschmann ◽  
Maria Svedendahl Humble ◽  
Jan‐E. Bäckvall

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