CARLOS ROBERTO JORGE SOARES

CARLOS ROBERTO JORGE SOARES

(Fonte: Lattes)

Resumo

Graduado em Farmácia e Bioquímica pela Universidade de São Paulo (1989), realizou Mestrado (1995) e Doutorado (2000) em Tecnologia Nuclear - Aplicações pela Universidade de São Paulo. Atualmente é pesquisador do Instituto de Pesquisas Energéticas (IPEN-CNEN/SP) e professor de pós-graduação vinculado à Universidade de São Paulo. Com experiência em biotecnologia na expressão de proteínas recombinantes por bactéria e por células de mamífero. Atua principalmente no seguinte tema: síntese, purificação, caracterização e aplicações de hormônios recombinantes. Atualmente é Gerente do Centro de Biotecnologia do IPEN. (Texto extraído do Currículo Lattes em 08 out. 2021)

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Periplasmic synthesis and purification of the human prolactin antagonist Δ1‑11‑G129R‑hPRL
2021 - SUZUKI, MIRIAM F.; ALMEIDA, LARISSA A.; POMIN, STEPHANIE A.; SILVA, FELIPE D.; FREIRE, RENAN P.; OLIVEIRA, JOAO E.; AFFONSO, REGINA; SOARES, CARLOS R.J.; BARTOLINI, PAOLO
The human prolactin antagonist Δ1-11-G129R-hPRL is a 21.9 kDa recombinant protein with 188 amino acids that downregulates the proliferation of a variety of cells expressing prolactin receptors. Periplasmic expression of recombinant proteins in E. coli has been considered an option for obtaining a soluble and correctly folded protein, as an alternative to cytoplasmic production. The aim of this work was, therefore, to synthesize for the first time, the Δ1-11-G129R-hPRL antagonist, testing different activation temperatures and purifying it by classical chromatographic techniques. E. coli BL21(DE3) strain was transformed with a plasmid based on the pET25b( +) vector, DsbA signal sequence and the antagonist cDNA sequence. Different doses of IPTG were added, activating under different temperatures, and extracting the periplasmic fluid via osmotic shock. The best conditions were achieved by activating at 35 °C for 5 h using 0.4 mM IPTG, which gave a specific expression of 0.157 ± 0.015 μg/mL/A600 at a final optical density of 3.43 ± 0.13 A600. Purification was carried out by nickel-affinity chromatography followed by size-exclusion chromatography, quantification being performed via high-performance size-exclusion chromatography (HPSEC). The prolactin antagonist was characterized by SDS-PAGE, Western blotting, reversed-phase high-performance liquid chromatography (RP-HPLC) and MALDI-TOF–MS. The final product presented > 95% purity and its antagonistic effects were evaluated in vitro in view of potential clinical applications, including inhibition of the proliferation of cancer cells overexpressing the prolactin receptor and specific antidiabetic properties, taking also advantage of the fact that this antagonist was obtained in a soluble and correctly folded form and without an initial methionine.
Expression of glycosylated human prolactin in HEK293 cells and related N‑glycan composition analysis
2019 - SILVA, FELIPE D.; OLIVEIRA, JOÃO E.; FREIRE, RENAN P.; SUZUKI, MIRIAM F.; SOARES, CARLOS R.; BARTOLINI, PAOLO
Prolactin (PRL) is a hormone produced by the pituitary gland with innumerable functions, such as lactation, reproduction, osmotic and immune regulation. The present work describes the synthesis of hPRL in human embryonic kidney (HEK293) cells, transiently transfected with the pcDNA-3.4-TOPO® vector carrying the hPRL cDNA. A concentration of ~ 20 mg/L, including glycosylated (G-hPRL) and non-glycosylated (NG-hPRL) human prolactin, was obtained, with ~ 19% of G-hPRL, which is higher than that observed in CHO-derived hPRL (~ 10%) and falling within the wide range of 5–30% reported for pituitary-derived hPRL. N-Glycoprofiling analysis of G-hPRL provided: (i) identification of each N-glycan structure and relative intensity; (ii) average N-glycan mass; (iii) molecular mass of the whole glycoprotein and relative carbohydrate mass fraction; (iv) mass fraction of each monosaccharide. The data obtained were compared to pituitary- and CHO-derived G-hPRL. The whole MM of HEK-derived G-hPRL, determined via MALDI–TOF-MS, was 25,123 Da, which is 0.88% higher than pit- and 0.61% higher than CHO-derived G-hPRL. The main difference with the latter was due to sialylation, which was ~ sevenfold lower, but slightly higher than that observed in native G-hPRL. The “in vitro” bioactivity of HEK-G-hPRL was ~ fourfold lower than that of native G-hPRL, with which it had in common also the number of N-glycan structures.