Specialty enzymes from cold adapted marine animals - bioprospecting, characterization and applications in model food systems

这项提案是我正在进行的海洋物种生物化学研究计划的延续，重点是冷适应酶。大多数酶被认为是“天然的”和可生物降解的，其使用伴随着“更环保”的结果和更低的环境影响。酶促反应具有选择性、一致性、可重复性、快速、高效和几乎没有不良副产物的特点。因此，酶已成为诊断、制药、研究和开发的重要工具；以及食品、饲料、生物燃料、洗涤剂、纸浆和造纸等市场。酶的需求稳步增长，预计到2018年全球工业酶市场将达到70亿美元，并在可预见的未来继续增长。尽管如此，酶促反应往往在狭窄的化学和物理条件范围内是最佳的，而大多数工业过程是在对酶的完整性有害的极端条件下进行的。因此，在恶劣的工业环境下，使用化学品仍然是最可行的选择。因此，迫切需要找到对环境更负责任的方法来取代可能有害的化学方法。能够承受工业环境的新型酶的发现对生物催化的未来至关重要。****有积极的研究，以发现新的酶，可以保持有效的工业应用。我的研究项目集中在从海洋动物中发现能在低温下发挥最佳作用的高级酶，并将其用于食品和相关应用。我们最近的一些研究包括从南极磷虾（Euphausia superba）和海参（Cucumaria frondosa）中发现了一种具有冷活性的TGase酶，这种酶可以促进水凝胶的冷凝固，用于食品的质地化和制作可生物降解的薄膜；2种鱿鱼（Loligo opalescens和Sepioteuthis lessoniana）的冷活性凝乳胰蛋白酶，并利用巢式PCR法测定其cDNA；以及一种来自灰鲻鱼（Mugil cephalus）的耐溶剂脂肪酶，我们将其固定化并用于从动物粪便中生产生物柴油。然而，依靠传统的鱼类收获作为工业酶的可持续来源是不现实的；因此，科学家们应该采用新兴的工具和技术来生产能够确保其稳定供应的特殊酶。在我们研究计划的下一阶段，我们将继续对不同的海洋酶进行生物勘探，确定它们的特征，利用重组DNA技术以更高的产量生产它们，并使它们以稳定的固定形式存在。该计划将在各个层次（研究生，研究生和本科生）培训HQP，并培养具备必要技能的个人，成为加拿大劳动力中的创新领导者，并维持生物催化的未来。******

This proposal is a continuation of my ongoing research program on the biochemistry of marine species, with focus on cold-adapted enzymes. Most enzymes are considered as “natural” and biodegradable whose uses are accompanied by “greener” outcomes and lower environmental impacts. Enzymatic reactions are selective, consistent, reproducible, fast, efficient, and practically devoid of undesirable by-products. Thus, enzymes have become vital tools for diagnostics, pharmaceuticals, research & development; and for markets such as food, feed, biofuels, detergents, pulp & paper. Demand for enzymes has grown steadily, with the global industrial enzymes market predicted to reach US $7 billion by 2018, and to continue to grow for the foreseeable future. Nonetheless, enzymatic reactions tend to be optimal within narrow ranges of chemical and physical conditions, while most industrial processes are conducted under extreme conditions that are harmful to enzyme integrity. Hence, the use of chemicals remains the most viable option under the harsh industrial settings. Thus, there is compelling need to find more environmentally responsible approaches to replace the potentially harmful chemical methods. The discovery of novel enzymes that can withstand industrial settings is crucial to the future of biocatalysis.****There is active research to discover novel enzymes that can remain efficient for industrial applications. My research program is focused on disclosing superior enzymes from marine animals that can function optimally at low temperatures and to exploit them in food and related applications. Some of our most recent studies include the discovery of a cold-active TGase enzymes from Antarctic krill (Euphausia superba) and sea cucumber (Cucumaria frondosa) that facilitate cold-setting of hydrogels for food texturization and for making biodegradable films; cold-active chymotrypsins from 2 squid species (Loligo opalescens & Sepioteuthis lessoniana), and the cDNA of the L. opalescens enzyme using nested PCR; and a solvent-resistant lipase from grey mullet (Mugil cephalus) that we immobilized and used to produce biodiesel from animal discards. However, it is not practical to rely on the traditional fish harvest as sustainable sources of industrial enzymes; thus, it behooves scientists to employ emerging tools and technologies to produce the specialty enzymes in forms that can assure their steady supply. In the next phase of our research program, we will continue bioprospecting for distinct marine enzymes, identify their distinguishing features, produce them in higher yields using recombinant DNA technology, and make them in stable immobilized forms. This program will train HQP at various levels (postgraduate, graduate & undergraduate) and produce individuals equipped with requisite skills to become innovation leaders in the Canadian workforce, and sustain the future of biocatalysis.******