Microbiology Exam 4 Part 4

Molecular cloning

Molecular cloning

Incorporation and isolation of a piece of DNA into a vector so it can be manipulated and replicated

Three main steps of molecular cloning (in sequential order)

Fragmentation and isolation of source DNA, insertion of DNA fragment into cloning vector, and introduction of cloned DNA into host organism

DNA used in molecular cloning

Recombinant DNA

Sticky ends

Single-stranded

Blunt ends

Double-stranded

Go together better (single-stranded sticky ends or double-stranded blunt ends?)

Single-stranded sticky ends

Molecular glue for recombinant DNA technology

T4 ligase

Qualities of plasmids that make good cloning vectors

Easy to purify, independent origin of replication (ori), multiple copy number, presence of selectable markers, small size (smaller than chromosome), and unique cloning sites (polylinker)

Example of common selectable markers for plasmids used as cloning vectors

Antibiotic resistance

The human body is a ___ environment

Diverse

Normal microbiota or microflora of the human body

Microbes associated with healthy body tissue and regularly found at an anatomical site

Symbiotic relationship between human body and microbiota/microflora begins at...

Birth

Symbiotic relationship between human body and microbiota/microflora varies...

With environment and food source

Microbiota/microflora found...

At mucous membranes and on surfaces of the body

Microbiota/microflora normally not found...

In internal tissues

Three microenvironments of skin

Dry skin, moist skin, and sebaceous skin

Skin has ___ microflora

Both resident and transient

Microflora of skin influenced by...

Environment and host factors

___ bacteria per square millimeter of skin

1 trillion

Skin microflora is ___ environment

Inhospitable

Skin microflora as inhospitable environment (5)

High concentration of NaCl, inhibitory substances, many areas low in moisture, mechanically strong barrier, and slightly acidic pH

Poor skin hygiene causes...

Acne vulgaris and body odor

Bacteria that causes acne vulgaris

Propionibacterium acnes

Outnumbers host cells

Skin bacteria