BiotechHiranyagarbha · Class 11-12
Insulin banane wala bacterium
Duniya bhar mein lakhon log roz insulin lete hain — banata use kaun hai?
Socho pehle… phir dekho jawab
Ek bacterium. Insaani insulin ka gene lab mein E. coli ke andar daal diya jaata hai, aur woh wahi protein banane lagti hai. Isi ko recombinant DNA technology kehte hain — do alag jeevon ka DNA jod kar ek naya kaam karwana.
Mechanism dekho. Restriction enzyme DNA ko ek palindromic sequence par kaat kar 'sticky ends' chhodta hai. Wahi enzyme plasmid par chalao toh dono ke ends fit ho jaate hain, aur DNA ligase unhe jod deta hai. Ab plasmid ek vector hai. Bioreactor mein bacteria badhte hain aur protein nikal aata hai. Insulin isi tarah bani: A aur B chain alag-alag banwa kar disulphide bond se jodi gayi.
PCR mein DNA 94°C par khulta hai, primers 50-60°C par chipakte hain, aur Taq polymerase 72°C par nayi chain banata hai. Har cycle mein copies double — n cycle ke baad 2ⁿ, yaani 30 cycle se lagbhag 10⁹ guna. DNA fingerprinting un repeat sequences par tiki hai jinki ginti har insaan mein alag hoti hai; Bharat mein yeh kaam CCMB, Hyderabad mein Lalji Singh ki team ne khada kiya tha.
Ab imaandar trade-off. Bt cotton mein Bacillus thuringiensis ka cry gene hai — paudha khud woh protein banata hai jo kuch keedon ke liye zeher hai; bollworm ka nuksaan aur kuch spray kam hue. Doosra pehlu: pink bollworm ne kai jagah resistance bana liya, beej mehenga hai, aur refuge lagana zaroori hai. CRISPR-Cas9 mein guide RNA enzyme ko theek us jagah le jaata hai jahan kaatna hai — aur yahin bioethics shuru hoti hai: somatic cells badalna aur germline badalna ek baat nahi. Pehla niyam: informed consent.
Ghar pe try karo
Do kagaz ki patti par ek hi sequence likho — GAATTC — aur haath se G ke baad phaad do. Dekho dono ke paas AATT ka jhoola bacha, jo sirf ek doosre se match karega: yahi sticky end hai. Phir calculator par 2^10, 2^20 aur 2^30 nikaalo — PCR ki taakat khud dikh jaayegi.
Wow!
Jo insulin aaj sabse surakshit maani jaati hai, use insaan ne nahi, ek bacterium ne banaya hai — hamare hi instruction par.
3 sawaal
- Recombinant DNA mein plasmid vector ka 'ori' kis kaam aata hai?
Jawab dekho
Host cell ke andar vector ki copy banna wahin se shuru hoti hai. Origin of replication ke bina vector host cell mein apni copies nahi bana paata.
- PCR mein 25 cycle ke baad ek DNA molecule se lagbhag kitni copies banengi?
Jawab dekho
2²⁵. Har cycle mein copies double hoti hain, toh n cycle ke baad 2ⁿ.
- Bt cotton ke baare mein kaunsa kathan sahi hai?
Jawab dekho
Kai jagah pink bollworm ne iske khilaaf resistance bana liya hai. Cry gene Bacillus thuringiensis naam ke bacterium se hai, aur lagatar selection pressure se keedon mein resistance aa sakta hai — isliye refuge ka niyam hai.
NCERT se jodo: NCERT Class 12 Biology — biotechnology: principles and processes; biotechnology and its applications