Public health issues and microbiology
Introduction
We are introduced to microorganisms from the moment of our birth when our fragile bodies are
exposed to the environment. Our mothers continue to protect us with antibodies gained from breast
milk. As we move towards adolescence, hormones explode and we experience a significant growth
spurt. As we continue aging into adulthood and later into our senior years, we begin to experience a
decline in physical and physiological activity.
Since ancient times cultures have recognized the problems related to development and aging, including
the increased susceptibility to infections and disease, both in the very young and the elderly.
From seeking the fountain of youth to cultural banishment of the elderly and sick, civilizations have been
attempting to deal with the problems and concerns associated with the human body as it goes through
the changes involved in the natural aging process.
Throughout our lives, the environment influences our potential to maintain health and wellness. The
environment experiences a similar process of growth and change.
This process is influenced by humans. A critical balance between humans and the environment results;
both respond to each other and changes as a result. Sometimes, the balance is not maintained and this
results in disasters of significant proportions. The changes that result in disasters frequently uncover
microorganisms that present problems and challenges, and it is the type and quality of response to
these disasters that helps to remediate or exacerbate the health issues presented.
Overview of genetic material in microorganisms
Before covering the topics of health and aging on immunocompetency, natural disasters on microbial
ecology and public health, and bioterrorism, a background in microorganisms’ genetics and ways they
mutate can be useful.
The functions of genetic material
DNA is the genetic material passed from parent to offspring and it serves as the information to direct
and regulate the construction of the proteins necessary for the cell to perform all of its functions.
Central dogma theory states that DNA is organized into genes that specifies the sequences of
messenger RNA (mRNA). mRNA, in turn, specifies the amino acid sequences of proteins.
The genotype of a cell is the full collection of genes a cell contains. The phenotype is a cell’s observable
characteristics resulting from the proteins it is producing at a given time under specific environmental
conditions.
, DNA replication
*the DNA replication process results in two DNA molecules, each having one parental strand of DNA and
one newly synthesized strand.
*in bacteria, the initiation of replication occurs at the origin of replication where supercoiled DNA is
unwound by DNA gyrase, made single-stranded by helicase, and bound by single-stranded binding
protein to maintain its single-stranded state.
*eukaryotes typically have multiple linear chromosomes, each with multiple origins of replication
*rolling circle replication-type of rapid unidirectional DNA synthesis of a circular DNA molecule used for
the replication of some plasmids (found in bacteria)
RNA Transcription
*during transcription, the information encoded in DNA is used to make RNA
*RNA polymerase synthesizes RNA using the DNA as template.
*RNA polymerase binds to DNA at a sequence called a promoter during the initiation of transcription
*eukaryotes have three different RNA polymerases.
Introduction
We are introduced to microorganisms from the moment of our birth when our fragile bodies are
exposed to the environment. Our mothers continue to protect us with antibodies gained from breast
milk. As we move towards adolescence, hormones explode and we experience a significant growth
spurt. As we continue aging into adulthood and later into our senior years, we begin to experience a
decline in physical and physiological activity.
Since ancient times cultures have recognized the problems related to development and aging, including
the increased susceptibility to infections and disease, both in the very young and the elderly.
From seeking the fountain of youth to cultural banishment of the elderly and sick, civilizations have been
attempting to deal with the problems and concerns associated with the human body as it goes through
the changes involved in the natural aging process.
Throughout our lives, the environment influences our potential to maintain health and wellness. The
environment experiences a similar process of growth and change.
This process is influenced by humans. A critical balance between humans and the environment results;
both respond to each other and changes as a result. Sometimes, the balance is not maintained and this
results in disasters of significant proportions. The changes that result in disasters frequently uncover
microorganisms that present problems and challenges, and it is the type and quality of response to
these disasters that helps to remediate or exacerbate the health issues presented.
Overview of genetic material in microorganisms
Before covering the topics of health and aging on immunocompetency, natural disasters on microbial
ecology and public health, and bioterrorism, a background in microorganisms’ genetics and ways they
mutate can be useful.
The functions of genetic material
DNA is the genetic material passed from parent to offspring and it serves as the information to direct
and regulate the construction of the proteins necessary for the cell to perform all of its functions.
Central dogma theory states that DNA is organized into genes that specifies the sequences of
messenger RNA (mRNA). mRNA, in turn, specifies the amino acid sequences of proteins.
The genotype of a cell is the full collection of genes a cell contains. The phenotype is a cell’s observable
characteristics resulting from the proteins it is producing at a given time under specific environmental
conditions.
, DNA replication
*the DNA replication process results in two DNA molecules, each having one parental strand of DNA and
one newly synthesized strand.
*in bacteria, the initiation of replication occurs at the origin of replication where supercoiled DNA is
unwound by DNA gyrase, made single-stranded by helicase, and bound by single-stranded binding
protein to maintain its single-stranded state.
*eukaryotes typically have multiple linear chromosomes, each with multiple origins of replication
*rolling circle replication-type of rapid unidirectional DNA synthesis of a circular DNA molecule used for
the replication of some plasmids (found in bacteria)
RNA Transcription
*during transcription, the information encoded in DNA is used to make RNA
*RNA polymerase synthesizes RNA using the DNA as template.
*RNA polymerase binds to DNA at a sequence called a promoter during the initiation of transcription
*eukaryotes have three different RNA polymerases.
