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L-asparaginase (L-asparagine amino hydrolase, E.C.3.5.1.1) is an enzyme clinically accepted as an antitumor agent to treat acute lymphoblastic leukemia and lymphosarcoma. It catalyzes L-asparagine (Asn) hydrolysis to L-aspartate and ammonia, and Asn effective depletion results in cytotoxicity to leukemic cells. Microbial L-asparaginase (ASNase) production has attracted considerable attention owing to its cost effectiveness and eco-friendliness. The focus of this review is to provide a thorough review on microbial ASNase production, with special emphasis to microbial producers, conditions of enzyme production, protein engineering, downstream processes, biochemical characteristics, enzyme stability, bioavailability, toxicity and allergy potential. Some issues are also highlighted that will have to be addressed to achieve better therapeutic results and less side effects of ASNase use in cancer treatment: (a) search for new sources of this enzyme to increase its availability as a drug; (b) production of new ASNases with improved pharmacodynamics, pharmacokinetics and toxicological profiles, and (c) improvement of ASNase production by recombinant microorganisms. In this regard, rational protein engineering, directed mutagenesis, metabolic flux analysis and optimization of purification protocols are expected to play a paramount role in the near future., This work was supported by grants from Brazil, specifically those financed by CAPES (reference numbers: #2805/2010 and #2609/2013), CNPq (reference number: #552652/2011-3) and FAPESP (reference numbers: #2013/08617-7 and #2013/19486-0).

The explanations of ritual practices observed in archaeological contexts often proceed on the representationalist basis that the human mind contains the social constituted ideas or representations that underpin the practice of rituals. Such a view remains widespread and, despite the often proclaimed rejection in contemporary theory of the Cartesian mind-body and other dualisms, it perpetuates the Enlightenment representationalist heritage according to which mental contents represent social reality and, as such, drive ritual practices and human action more generally. This article illustrates the meaning and value of rejecting such a representationalist view of human (ritual) action in favour of what we call an institutional view. In such a view, a ritual can be conceived as a form of recurring activity involving temporally and geographically dispersed actors active in differing roles and hence also with differing interests and levels of knowledge of the ritual and the associated belief system.

Elastin-like recombinant protein polymers are a new family of polymers which are captivating the attention of a broad audience ranging from nanotechnologists to biomaterials and more basic scientists. This is due to the extraordinary confluence of different properties shown by this kind of material that are not found together in other polymer systems. Elastin-like polymers are extraordinarily biocompatible, acutely smart and show uncommon self-assembling capabilities. Additionally, they are highly versatile, since these properties can be tuned and expanded in many different ways by substituting the amino acids of the dominating repeating peptide or by inserting, in the polymer architecture, (bio)functional domains extracted from other natural proteins or de novo designs. Recently, the potential shown by elastin-like polymers has, in addition, been boosted and amplified by the use of recombinant DNA technologies. By this means, complex molecular designs and extreme control over the amino-acid sequence can be attained. Nowadays, the degree of complexity and control shown by the elastin-like protein polymers is well beyond the reach of even the most advanced polymer chemistry technologies. This will open new possibilities in obtaining synthetic advanced bio- and nanomaterials. This review explores the present development of elastin-like protein polymers, with a particular emphasis for biomedical uses, along with some future directions that this field will likely explore in the near future.

(1992). Institutional sources of corruption in Brazil. Third World Quarterly: Vol. 13, No. 4, pp. 641-661.