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The effect of four NH4:NO3 ratios in the nutrient solution (0:100; 25:75; 50:50 and 75:25) on growth and nutrient concentrations of four kale (Brassica oleraceae L. var. acephala) hybrids: ‘CN KAL 1029’, ‘Redbor’, ‘Winnetou’, ‘Reflex’ and one indigenous cultivar: ‘Ntopia Mytilinis’ was investigated. In the first four weeks of cultivation none of the NH4/NO3 ratios applied induced adverse effects on most growth characteristics determined whereas plants grown with 75% NH4-N accumulated higher leaf N, P, K, Fe, Mn, Zn and Cu concentrations. After an eight week period, plants under 75% NH4-N showed significant reductions in many growth parameters suggesting a probable preference of kale plants grown for a prolonged period towards either a complete exclusion of NH4 from the nutrient solution or a 25:75 or a 50:50 NH4/NO3 ratio. Among the genotypes tested, ‘Ntopia Mytilinis’ produced the greatest yield with the lowest leaf nitrate accumulation. ********* In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number (Volume 47, Issue 3, 2019). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue. *********

The group IVA cytosolic phospholipase A(2) (GIVA cPLA(2)) plays a central role in inflammation. Long chain 2-oxoamides constitute a class of potent GIVA cPLA(2) inhibitors that exhibit potent in vivo anti-inflammatory and analgesic activity. We have now gained insight into the binding of 2-oxoamide inhibitors in the GIVA cPLA(2) active site through a combination of molecular docking calculations and molecular dynamics simulations. Recently, the location of the 2-oxoamide inhibitor AX007 within the active site of the GIVA cPLA(2) was determined using a combination of deuterium exchange mass spectrometry followed by molecular dynamics simulations. After the optimization of the AX007-GIVA cPLA(2) complex using the docking algorithm Surflex-Dock, a series of additional 2-oxoamide inhibitors have been docked in the enzyme active site. The calculated binding affinity presents a good statistical correlation with the experimental inhibitory activity (r(2) = 0.76, N = 11). A molecular dynamics simulation of the docking complex of the most active compound has revealed persistent interactions of the inhibitor with the enzyme active site and proves the stability of the docking complex and the validity of the binding suggested by the docking calculations. The combination of molecular docking calculations and molecular dynamics simulations is useful in defining the binding of small-molecule inhibitors and provides a valuable tool for the design of new compounds with improved inhibitory activity against GIVA cPLA(2).