TERBENTUKNYA TURUNAN “BARU”
1. KAWIN SILANG - SEKSUAL
2. PARASEKSUAL
• ANTIBODI MONOKLONAL EVOLUSI
SINAR MATAHARI-KOSMIS POLUTAN / CEMARAN
BIBIT UNGGUL DARI BIJI TOKSISITAS OBAT
• TANAMAN UNGGULAN
TERBENTUKNYA TURUNAN BARU
( INSULIN, VAKSIN-HB )
PERUBAHAN GEN --> FENOTIP DAN PRODUK BARU
• TURUNAN UNGGULAN YANG SAMA
• UNGGULAN PRODUK BARU
RESISTENSI MIKROBA
PATOGEN
TERHADAP ANTIBIOTIK
1. Bakteri
2. Virus
Bacterial cells divide by the process of binary fission. A cell will first
duplicate its chromosome, elongate, and then pinch in the middle creating
two genetically identical daughter cells.
During replication of the chromosome, there is no built in repair
mechanism, so if mistakes occur during replication they will be passed on
to daughter cells. Some mistakes have no effect on the bacterial cell. Other
mistakes can create fatal errors and the cell will die. However, some
Bacterial cells divide by the process of binary fission. A cell will first
duplicate its chromosome, elongate, and then pinch in the middle creating
two genetically identical daughter cells.
2. GEN FOR ANTIBIOTIC ALTERING ENZYME/TARGET
3. GEN FOR ANTIBIOTIC
DEGRADING ENZYME
1. GENE FOR “EFFLUX” PUMPS THAT EJECT ANTIBIOTICS
FROM CELL
ANTIBIOTIC-RESISTANT BACTERIA
HOW - WHY ?
TRANSFORMASI
KONYUGASI
TRANSDUKSI
BACTERIA PICK UP
sensitive bacterium
sensitive bacterium
resistance bacterium
DNA-frament = resistance gene
BACTERIA PICK UP RESISTANCE GENES from other bacterial cells in three main ways.
Often they receive whole plasmids bearing one or more such genes from a donor cell (a).
Other times, a virus will pick up a resistance gene from one bacterium and inject it into a different bacterial cell (b).
Alternatively, bacteria sometimes scavenge gene-bearing snippets of DNA from dead cells in their vicinity (c).
Genes obtained through viruses or from dead cells persist in their new owner if they become incorporated stably into the recipient's chromosome or into a plasmid.
ANTIBIOTIC-RESISTANT BACTERIA owe their drug insensitivity to resistance genes. For example, such genes
might code for "efflux" pumps that eject antibiotics from cells (a). Or the genes might give rise to enzymes that degrade the antibiotics (b) or
that chemically alter--and inactivate--the drugs (c).
Genetic Basis of Acquired Resistance
1. Mutation
- spontaneous alteration in genetic sequence in
bacterial chromosome
2. Conjugation
- transfer of genetic information via
conjugation tubes
3. Transduction
(bacteriophage) - phage incorporation of
genetic information which can then be transferred to
another bacterium
4. Transformation
- possible assimilation of genetic material
across cell wall/membrane
Location: plasmids, transposons, chromosome
Phenotypic Mechanisms of Resistance
1. Enzyme degradation
Antibiotic resistance results from gene action. Bacteria
acquire genes conferring resistance in any of three ways
In spontaneous DNA mutation, bacterial DNA (genetic material) may mutate (change)
spontaneously (indicated by starburst). Drug-resistant tuberculosis arises this way.
In a form of microbial sex called transformation, one bacterium may take up DNA from another
bacterium. Pencillin-resistant gonorrhea results from transformation
ONE PHARMACEUTICAL STRATEGY for overcoming resistance capitalizes on the discovery that some bacteria defeat certain
antibiotics, such as tetracycline, by pumping out the drugs (a). To combat that ploy, investigators are devising compounds that