Решения проблем фолдинга белков для повышения эффективности дрожжевых биопродуцентов

За последние несколько десятилетий дрожжи стали наиболее эффективными биопродуцентами рекомбинантных белков с различными потребительскими свойствами. Это стало возможным благодаря их экономически выгодным характеристикам и успешному применению генно-инженерных технологий. Кроме того, дрожжи обладают консервативным для эукариотических организмов механизмом посттрансляционной модификации белков, который обеспечивает их корректный фолдинг, необходимый для дальнейшей секреции и функциональной активности. Однако аппарат фолдинга не всегда справляется с нагрузкой, вызванной сверхэкспрессией рекомбинантных генов, что приводит к накоплению неправильно свернутых белков, образованию агрегатов и низкой продуктивности дрожжевых штаммов. Таким образом, способность к фолдингу белков в эндоплазматическом ретикулуме по-прежнему остается одним из основных ограничений при синтезе рекомбинатных белков в дрожжевых клетках. Эти ограничения были в значительной степени преодолены благодаря многолетним эффективным исследованиям фундаментальных механизмов белкового фолдинга. Изучение фолдинга как у модельных организмов, так и у биопродуцентов позволило выявить молекулярные факторы и клеточные механизмы, определяющие формирование трехмерной функциональной структуры растущей пептидной цепи. Полученные знания легли в основу разработки новых эффективных методов конструирования высокопродуктивных штаммов дрожжей. В данном обзоре мы рассмотрели основные клеточные механизмы, связанные с фолдингом белков, такие как транспорт через эндоплазматический ретикулум, взаимодействие с шаперонами, окислительный фолдинг, гликозилирование и контроль качества белков. Мы обсудили эффективность применения этих знаний при разработке различных инженерных методов, направленных на преодоление узких мест в системе белкового фолдинга. В частности, подбор оптимальных сигнальных пептидов, коэкспрессия с шаперонами и фолдазами, модификация клеточных механизмов контроля качества белков, ингибирование протеолиза и некоторые другие приемы позволили повысить возможности использования дрожжей-продуцентов в качестве эффективной производительной платформы для экспрессии и секреции рекомбинантных белков.

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