Jovan Hranisavljevic

Synthesis and estrogen activity screening of some new D-secoestrone derivatives.

Five new D-secoestrone derivatives were synthesized, starting from 3-methoxy-17-hydroxy-16,17-secoestra-1,3,5(10)-triene-16-nitrile. Newly synthesized compounds showed a complete loss of estrogenic activity.

Isolation and Characterization of Highly Liganded Protein from Brewer's Barley Grain

Two basic proteins, HLP-1 and HLP-2, were isolated from brewers barley grain (Hordeum vulgare L.) and characterized as glycoproteins with molecular masses of 16 and 13 kDa and pI values of 7.4 and 8.8, respectively. They could bind sugars, metal ions, and both hydrophobic and hydrophylic molecules of low molecular mass. These characteristics may be related to their potential plant-protecting role.

Isolation and characterization of isoforms of retinol binding protein by isoelectrofocusing

Retinol binding protein prepared from human urine was fractionated by chromatofocusing into four isoforms: two retinol‐containing (holo‐) and two retinol‐free (apo‐) species. The pI values of the isoforms ascertained by isoelectrofocusing with an immobiline pH gradient were: holo(I) 4.79‐4.77; apo(II) 4.61‐4.56; holo(III) 4.63 and apo(IV) 4.46‐4.41. In vitro aging experiments with apo(II) under conditions favoring deamidation (37°C, pH 7‐10, 3‐28 days) resulted in formation of the more acidic apo(IV)‐isoform. The aging rate was consistent with pH increase. It appears that the urinary RBP mixture is composed of two apo‐holo pairs: a native form with genuine protein structure and an acidic form generated upon aging.