creating living systems. it is easy to ask questions in biology it is difficult to answer and we try...

Creating living systems

• It is easy to ask questions in biology

• It is difficult to answer

• And we try to use words like

Conformation

Flexibility

Evolution

complexity

Living System???

More of a paradox!!!!

Chemical composition of cell

(Can we design a Cell?)

Paradoxes in Living System

Assumptions!!!

• Can I create a Cell

• Reductionist approach

(Break a cell and see)

Chemical composition of a Cell

Give me my Cell Back!!!!

However Craig Venter was able to think out of the box

1995

Can a complete genetic system be reproduced by chemical synthesis starting

with only the digitized DNA sequence contained in a computer?

Build a cell which contains only essential genes

Mycoplasma genitalium, a bacterium with the smallest complement of genes of any known organism capable of independent growth in the laboratory

Mycoplasma laboratorium or Mycoplasma JCVI-1.0

There is speculation that this line of research could lead to producing bacteria that have been engineered to perform specific reactions, e.g. produce biofuels, make medicines, combat global warming, etc

partially synthetic species of bacterium derived from the genome of Mycoplasma genitalium called Mycoplasma laboratorium. (smallest known free-living bacterium, and the second-smallest bacterium and also considered to be the organism with the smallest genome (482 genes and 582,970 base pair genome ) till 2002

Craig Venter and Nobel laureate Hamilton Smith

MYCOPLASMA MYCOIDES

SYNTHETIC BACTERIA

MYCOPLASMA CAPRIOLUM

SYNTHESIZED DNA IN A TEST TUBE

PUT IT HERE

Mycoplasma mycoides JCVI-syn1.0 - the world's first synthetic

organism

First truly synthetic organism created using four bottles of chemicals and a computer

Creating a synthetic cell

Applications

• You can make cells with some genes for living and the other genes for

• Biofuel

• Biopesticide

• Drugs

Advantages

We can make cells with few genes required for survival and few for making

BiofuelsDrugsBiopesticidesbioplastic

Major risks

• Bioterrorism

The synthetic cell theory again supports the fact that life did not originate in earth but life appeared

from somewhere.

The other theory:

Life originated in earth

RNA was the first genetic material

(RNA world)

MILLER UREY EXPT

RNAPROTEINS

SPONTANEOUSLY

Flow of Genetic Information

Reverse Transcription

RNA

PROTEIN

RNA

DNA

DNA

PROTEIN

RNARNA

PROTEIN

RNA

RNA can act as genetic material

• HIV

RNA acts as Enzymes

“RIBOZYMES”

Life originated in water

O Base

H

OH

HH

H

O

P

CH2

O

P

..

1'

2'3'

4'

5'

CHO

H2COH

OH

OH

OH

H

H

H

1'

2'

3'

4'

5'

D-Ribose(open Chain Str.)

-D-Ribofuranose residue in polynucleotide Chain

:B

Stepping back conceptually from our parochial water-dominated viewpoint, we can immediately see that water is really a noxious, toxic, corrosive and generally lethal environment for life. In fact given the well known properties of water one might almost be tempted to say that it’s a miracle that life ever began in such a solvent!

Explaining the Universe Without a Clue

Jack W. Szostak

Life originated in ammonia