基因工程學產物 : 重組蛋白質

蛋白質DNA( 基因 ) mRNA

胰島素缺乏 糖尿病

如胰島素 , 干擾素等 (93 億美元 , 北美 ,1997)

Restriction enzyme

Restriction fragment length polymorphism

Nonautonomous retrotransposonsencode no protein

• Alu elements contain the sequence AGCT that is recognized by the restriction enzyme AluI. They are present in up to a million copies in the human genome.

• They can not transpose by themselves. Instead they take advantage of the retrotransposition machinery of other elements, such as LINEs.

Inducer: IPTG,lactose

Cut lactose and x-gal

重組蛋白質在寄主 (host) 細胞中的表達

E. coli

染色體

質體

基因

優點•產量大•操作易

缺點•no post-translation modification•inclusion body•not secrete protein

4,000kb

重組蛋白質在寄主細胞中的表達

E. coli gram-positive bacteria 缺點 B. subtilis

not secrete protein proteases

limited vector & promoter

“signal” has not found yet

Figure 22.23DNA library

基因工程學

昆蟲細胞

染色體

基因

細胞核

病毒

•基因治療•基因食物

receptor

常見的動物細胞寄主

insect cell-baculovirus

mammal-retrovirus

chinese hamster ovary (CHO) cells

immortal cell

基因工程學

•單株抗體生產 Hybridoma

•桃莉羊 無細胞核受精卵 + 體細胞細胞核

質體不穩定

Growth inhibition

0

0.2

0.4

0.6

0.8

1

1.2

0 5 10 15 20 25 30

LuxA (% total protein)

(B)

Td with plasmid = 45 min

τ d without plasmid = 30 min

Np = 2T/45×Np0

Nn,p = 2t/30×Nn,p0

一天後：

Np = 232×Np0

Nn,p = 248×Nn,p0

→ Np/Nn,p = Np0/216×N,p0

30 天後：

Np = 2960×Np0

Nn,p = 21440×Nn,p0

→ Np/Nn,p = Np0/2480×N,p0

使用 chemostat為 bioreactor其產量將遠大於 batch。可是為什麼工業界使用 batch的比率遠高於 chemostat？

1.Secondary products

2.Genetic instability

3.Operability and reliability 4.Market economics