Estudo sobre a interação entre a heme oxygenase - 1 e a HBP humana

Mestrado em BiotecnologiaThe presented work aimed to examine for the first time the interaction between heme oxygenase -1 (HO-1) and heme bound human HBP (hHBP). The protein hHBP is thought to be a heme binding protein involved in heme transport during heme metabolism in cells, although the exact function is unknown. Heme binds with a mM Kd. Therefore if hHBP is being used to transport heme, a partner needs to be present to accept the heme ring. Unpublished results have shown that HO-1 is present when hHBP is knocked down in hepatic cell moodels, therefore HO-1 could be possible partner for hHBP. Both proteins were overexpressed in a bacterial host system. HO-1 was grown in non isotopically labeled media while hHBP was grown in M9 media with 15N, labeling. hHBP was purified using affinity chromatography while anion exchange chromatography was used for HO-1. To initially study the binding of heme to HO-1 UV-vis spectroscopy was used with the heme absorbance at 405nm being followed. Binding was observed as expected. Heme tritration with HO-1, hHBP and mixtures of hHBP/HO-1 were carried out to follow the fate of the heme molecule. NMR spectroscopy was also used to see if HO-1 could remove heme from heme-bound hHBP. The results indicate that HO-1 cannot in fact remove heme from hHBP

Keratinases as Versatile Enzymatic Tools for Sustainable Development

To reduce anthropological pressure on the environment, the implementation of novel technologies in present and future economies is needed for sustainable development. The food industry, with dairy and meat production in particular, has a significant environmental impact. Global poultry production is one of the fastest-growing meat producing sectors and is connected with the generation of burdensome streams of manure, offal and feather waste. In 2020, the EU alone produced around 3.2 million tonnes of poultry feather waste composed primarily of keratin, a protein biopolymer resistant to conventional proteolytic enzymes. If not managed properly, keratin waste can significantly affect ecosystems, contributing to environmental pollution, and pose a serious hazard to human and livestock health. In this article, the application of keratinolytic enzymes and microorganisms for promising novel keratin waste management methods with generation of new value-added products, such as bioactive peptides, vitamins, prion decontamination agents and biomaterials were reviewed

Extremophilic and modified aminotransferases as a versatile tool for the synthesis of optically pure building blocks for pharmaceutical industry

Considerable progress has been made in the past few years with industrial use of essential key intermediates for chemical and pharmaceutical industry. The increasing demand for obtaining chiral drugs in enantiomerically pure form makes it necessary to search for novel biocatalysts useful in the synthesis of amino acids, chiral amines, amino sugars and alcohols. According to the reaction mechanism, aminotransferases (ATs) have useful applications because of their capability of transfer of an amino group from a donor substrate to an acceptor, thus resulting in the synthesis of a wide variety of building blocks. This article reviews current biocatalytic approaches using microbial ATs in the synthesis of optically active products. Focus is also put on the engineering of ATs and their limitations in the industrial applications. Moreover this review covers biocatalytic approaches using ATs isolated from extreme environments