Cách tạo ra chủng sinh vật mới

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Giải thích các bước giải:

Kĩ thuật gen được ứng dụng để tạo ra các chủng vi sinh vật mới có khả năng sản xuất nhiều loại sản phẩm sinh học (axit amin, prôtêin, vitamin, enzim, hoocmôn, kháng sinh...) với số lượng lớn và giá thành rẻ.

Như ta đã biết, tế bào nhận được dùng phố biến hiện nay là E. coli (vi khuẩn đường ruột) và nấm men. Chúng có ưu điểm là để nuôi cấy và có khá năng sinh sản rất nhanh, dẫn đến tăng nhanh số bản sao của gen được chuyển. Tế bào E. coli sau 30 phút lại nhân đôi. Sau 12 giờ, một tê bào ban đầu sẽ sinh ra 16 triệu tê bào.

Những điều nêu trên giúp ta hiểu rõ tại sao dùng chủng E. coli được cấy gen mã hoá hoocmôn insulin ở người trong sản xuất thì giá thành insulin đê chữa bệnh đái tháo đường rẻ hơn hàng vạn lần so với trước đây phải tách chiết từ mô động vật. Tương tự như vậy, người ta đã sừ dụng vi khuẩn E. coli được chuyển gen từ xạ khuẩn để nâng cao hiệu quả sản xuất các chất kháng sinh.

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