In Arabidopsis, maturation phase, an intricate process in seed formation is tightly regulated by the DNA binding activity of protagonist basic leucine zipper 53 (bZIP53) transcription factor and its heterodimerizing partners, bZIP10 and bZIP25. Structural determinants responsible for heterodimerization specificity of bZIP53 are poorly understood. Analysis of amino acid sequences of three bZIPs does not identify interactions that may favor heterodimerization. Here, we describe a designed dominant negative termed A-ZIP53 that has a glutamic acid-rich amphipathic peptide sequence attached to N-terminal of bZIP53 leucine zipper. Circular dichroism (CD) and mass spectrometry studies with equimolar mixture of three bZIP proteins in pairs showed no heterodimer formation whereas A-ZIP53 interacted and formed stable heterodimers with bZIP53, bZIP10, and bZIP25. A-ZIP53 electrostatically mimics DNA and can overcome repulsion between basic DNA binding regions of three bZIP proteins. Gel shift experiments showed that A-ZIP53 can inhibit the DNA binding of three proteins. CD studies demonstrated the specificity of A-ZIP53 as it did not interact with bZIP39 and bZIP72. Transient co-transfections in Arabidopsis protoplasts showed that A-ZIP53 inhibited three bZIPs and their putative heterodimers-mediated transactivation of GUS reporter gene. Furthermore, four newly designed acidic extensions were evaluated for their ability to interact with three bZIPs.

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Starch makes up 70% of the wheat grain, and is an important source of calories for humans, however, the overconsumption of wheat starch may contribute to nutrition-associated health problems. The challenge is to develop resistant starch including high amylose wheat varieties with health benefits. Adapting advance genomic approaches in EMS-induced mutant lines differing in amylose content, basic leucine zipper (bZIP) regulatory factors that may play role in controlling amylose biosynthesis were identified in wheat. bZIP transcription factors are key regulators of starch biosynthesis genes in rice and maize, but their role in regulating these genes in wheat is poorly understood. A genome-wide survey identified 370 wheat bZIPs, clustered in 11 groups, showing variations in amino acids composition and predicted physicochemical properties. Three approaches namely, whole transcriptome sequencing, qRT-PCR, and correlation analysis in contrasting high and low amylose mutants and their parent line identified 24 candidate bZIP (positive and negative regulators), suggesting bZIPs role in high amylose biosynthesis. bZIPs positive role in high amylose biosynthesis is not known. In silico interactome studies of candidate wheat bZIP homologs in Arabidopsis and rice identified their putative functional role. The identified bZIPs are involved in stress-related pathways, flower and seed development, and starch biosynthesis. An in-depth analysis of molecular mechanism of novel candidate bZIPs may help in raising and improving high amylose wheat varieties.

In pursuit of better anti-HIV drugs, quantitative structure-activity relationship (QSAR) studies were performed on a series of aryl sulfonamide HIV protease inhibitors using Win CAChe 6.1. Multiple linear regression analysis was performed to derive QSAR models, which were further evaluated for statistical significance and predictive power by internal and external validation. The QSAR model indicates that the thermodynamic descriptors (heat of formation, log P, and molar refractivity) and steric descriptor (solvent assessable surface area) play an important role for the anti-HIV activity. The results of the present study may be useful on the designing of more potent anti-HIV agents.

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(9) were synthesized to model the stoichiometric, coordination, and protonation chemistry in the waxy metallosurfactants 1-4. Detailed data analysis and comparison between 1-4 and 5-9 involved mass spectrometric and spectroscopic methods along with crystallographic determination of 5 (P2 1 /c), 6 (P1), 7 (P2 1 /c), 8Ј (the analogue of 8 with tetraphenylborate counterions, P2 1 /c), and 9 (P1). DFT calculations were used to identify the frontier orbitals, polarizability, and dipole moments. Species 1-4 had their

O flurbiprofen (FB) apresenta efeitos colaterais comuns às drogas do tipo NSAIDs (Nonsteroidal anti-inflammatory drugs-drogas não esteróides anti-inflamatórias), devido à presença do grupo carboxílico livre. O objetivo desse estudo foi retardar esses efeitos adversos de origem gastrointestinal. Dez pró-fármacos derivados do FB foram sintetizados por amidação com ésteres etílicos de amino-ácidos, a saber: glicina, L-fenilanilina, L-triptofan, L-valina, L-isoleucina, L-ácido glutâmico, L-ácido aspártico e alanina. Os pró-fármacos sintetizados e purificados foram caracterizados por m.p., TLC, solubilidade, coeficientes de partição, análise elementar, UV, FTIR, NMR e MS. Foram submetidos também a estudos de biodisponibilidade, à atividade analgésica e anti-inflamatória e ao índice ulcerogênico. Os resultados obtidos mostraram redução acentuada do índice ulcerogênico e das atividades analgésica e anti-inflamatória comparáveis em todas os casos em relação ao FB. Os pró-fármacos sintetizados AR-9, AR-10 e AR-2 apresentaram uma excelente resposta farmacológica e velocidade de hidrólise encorajadoura em ambos os testes com SIF (Simulated Intestinal Fluid) e com plama humano a 80%. Os pró-fármacos com cadeia lateral aumentada ou com um substituinte aromático apresentam um melhor coeficiente de partição. Contudo, a solubilidade e a velocidade de hidrólise decresceram. Tais pró-fármacos podem ser considerados para uso com liberação sustentável. Flurbiprofen (FB) suffers from the general side effects of NSAIDs, owing to presence of free carboxylic acid group. The study was aimed to retard the adverse effects of gastrointestinal origin. Ten prodrugs of FB were synthesized by amidation with ethyl esters of amino acids, namely, glycine, L-phenylalanine, L-tryptophan, L-valine, L-isoleucine, L-alanine, L-leucine, L-glutamic acid, L-aspartic acid and alanine. Purified synthesized prodrugs were characterized by m.p., TLC, solubility, partition coefficients, elemental analyses, UV, FTIR, NMR and MS. Synthesized prodrugs were subjected for bioavailibility studies, analgesic, anti-inflammatory activities and ulcerogenic index. Marked reduction of ulcerogenic index and comparable analgesic, antiinflammatory activities were obtained in all cases as compared to FB. Among synthesized prodrugs AR-9, AR-10 and AR-2 showing excellent pharmacological response and encouraging hydrolysis rate both in (Simulated Intestinal Fluid) SIF and in 80% human plasma. Prodrugs with increased aliphatic side chain length or introduction of aromatic substituent resulted in enhanced partition coefficient but diminished dissolution and hydrolysis rate. Such prodrugs can be considered for sustained release purpose.

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