INTERNAL BACTERIAL STRUCTURE Flashcards
- Gram: Both gram positive (+) and gram negative (-)
- Chemical composition: DNA; RNA; Proteins
- Function: Genetic material (all essential genes)
- Remember: DNA and RNA of a prokaryotic cell (bacteria) is
not bounded by a nuclear membrane; therefore, they are
scattered in the cytoplasm (that is why there exists a
Nucleoid Region).
NUCLEOID REGION (NUCLEAR BODY/CHROMATIN BODY/
NUCLEAR REGION)
- Gram: Both gram positive (+) and gram negative (-)
- Chemical composition: DNA
- Function:
o Non-essential genetic material
o Roles in conjugation (by Sex Pili), drug
resistance, and toxin production.- Plasmids are extra-chromosomal DNA.
PLASMIDS
- Gram: Both gram positive (+) and gram negative (-)
- Chemical composition: 70s, 30s, 50s (Bacterial species)
o S stands for Svedberg (unit for Ribosomes) - Function:
o CHON Synthesis (Protein Synthesis)- In comparison, eukaryotes also have ribosomes, but it is made up of 60s, 40s, and 80s.
RIBOSOMES
- Gram: Both gram positive (+) and gram negative (-)
- Chemical composition: Glycogen, Lipids, Polyphosphate, etc.
- Function: Storage
GRANULES
MICROORGANISMS THAT POSSESS GRANULES
- Corynebacterium
- Mycobacterium
- Yersinia Pestis
Metachromatic granules (AKA Babes’-Ernest Granules) – for food storage
Corynebacterium
Much Granules
Mycobacterium
Yersinia Pestis
Volutin Granules
- Gram: Gram positive (+) only
- Chemical composition: Keratin coat, Calcium dipicolinate
- Function: Resistance to heat, chemicals, and dehydration.
* Endospores are vegetative forms of
microbes wherein they lay dormant
for years and replicate when the
desired environment is achieved.
ENDOSPORES
Two microorganisms that possess endospores
Bacillus and Clostridium.
made up of monomer building blocks called nucleotides
Nucleic acids
Adenine
Guanine
- Composed of two
carbon-nitrogen
closed rings (2
nitrogen per ring
=4) Larger
Purines
Cytosine
Thymine
Uracil
Composed of one
carbon-nitrogen
closed ring (2
nitrogen)
Smaller
Pyrimidines
always double-stranded or they are in
helical form.
Each base is complementary with one another.
o Each base is bonded by hydrogen bonds.
DNA structure
enzymes remove/destroy the hydrogen bonds so the coiled DNA will separate and undergo replication.
Helicase
- Show more variety in the nature of their genomes than do
cells - Can be DNA or RNA; never both.
- The primary way scientists categorize and classify viruses.
- Can be dsDNA, ssDNA, dsRNA, or ssRNA
- May be linear and composed of several segments or single
and circular. - It is much smaller than genomes of cells
GENETIC MATERIAL OF VIRUSES
- Replication: The process of copying DNA.
- Think of “duplication”
- Happens in all types of cells, prokaryotes and eukaryotes.
COPYING DNA
- After the genetic material is copied, the prokaryotic cell divides — a process called______ in which two
identical daughter cells arise from one parent cell.
binary fission
= After the genetic material is copied, the prokaryotic cell divides — a process called binary fission, in which two identical daughter cells arise from one parent cell
= At one-point isang bacteria na bilog. When copying of genetic material occurs, they will divide by binary fission and the
parent cell will produce 2 daughter cells
= With that division, we can compute the generation time for a
specific organism.
= For instance, E. Coli, to have a sufficient bacterial load, it needs 15-20 mins to have a million of these bacteria.
PROKARYOTE GENETICS: CELL DIVISION
- Mitosis: A single cell divides into two identical daughter cells. It is essential for growth and repair in both single-cell and
multicellular organisms - Meiosis: It produces sex cells, and its main purpose is for sexual reproduction. Daughter cells are not identical.-
EUKARYOTE GENETICS: CELL DIVISION
A single cell divides into two identical daughter cells. It is essential for growth and repair in both single-cell and
multicellular organisms
Mitosis
It produces sex cells, and its main purpose is for sexual reproduction. Daughter cells are not identical.
Meiosis
It is the process by which the DNA directs the synthesis of hnRNA/mRNA molecules that carry the coded information needed for protein synthesis.
Transcription
It is the process by which mRNA codons are deciphered and a particular protein molecule is synthesized.
Translation
- Our chromosomes are similar, but the only difference is the protein because →
the protein holds our genetic material
WHAT BASE DOES RNA HAVE THAT DNA DOESN’T HAVE?
Uracil
WHAR BASE DOES DNA HAVE THAT RNA DOESN’T HAVE?
Thymine
- Replication: The process of copying DNA
- To make RNA, the DNA will undergo the process of Transcription
o It is a process by which a DNA
sequence is copied to produce a
complementary RNA. - In other words, it is the transfer of genetic information from
DNA into RNA. - Like replication, but we are making RNA
- Beginning of the process that ultimately leads to the translation of the genetic code (via mRNA) into a peptide or
protein
PROTEIN SYNTHESIS
o It is like a blueprint, it is the copy of information in DNA that is brought to the ribosome where the information is translated into a protein.
Messenger (mRNA)
It is like a factory. It is the protein factories of the cells.
Ribosomal (rRNA)
o It is like a delivery truck. It brings the amino acids to the ribosome
Transfer (tRNA)
- Next thing to do in making a protein is to use the instructions delivered by RNA to make a protein molecule.
- Ribosomes make proteins from the messages encoded in mRNA.
TRANSLATION
WHERE DOES TRANSLATION OCCUR?
Prokaryotes:
Cytoplasm
WHERE DOES TRANSLATION OCCUR?
Eukaryotes:
Outside the nucleus in the cytoplasm
Many strains of Staphylococcus are now resistant to_______
- Gene for beta-lactamase is only expressed (turned on) in the
presence of__________
When the bacteria is not exposed to _____ that gene is turned off and no beta-lactamase is made
penicillin
One bacterial protein that confers penicillin resistance is called _____ → It is an enzyme that cuts up and deactivates penicillin.
Understanding how ______ is turned on/off can help us to design a drug to disable that gene expression (turn off
the gene), making penicillin-resistant strains of Staph vulnerable to penicillin.
beta-lactamase
When a recipient cell takes up DNA from the environment (such as DNA released from a dead organism)
TRANSFORMATION
- In 1928, Frederick Griffith discovered this process while trying to develop a vaccine for pneumonia caused by_____
Streptococcus pneumoniae
_____ had a protective capsule and caused deadly pneumonia when injected into mice.
S strain