Ch. 8 Microbial Genetics & Genetic Engineering

What are differences between eukaryotic and bacterial protein synthesis?

-Transcription and translation are simultaneous in bacteria but not eukaryotes -The first amino acid is slightly different

Which two types of horozontal gene transfer do NOT require direct contact between the donor and the recipient cells?

-Transduction -Transformation

What methods are used in gene transfer in bacteria?

-Transformation -Transduction -Conjugation

Photoactivation to repair DNA damage requires what?

-Visible light -DNA photolyase

Recombinant human insulin is produced from:

-Yeast -Bacteria

What describes the origin of replication?

-located on the chromosome -AT-rich

A Nitrogen- containing molecule found in DNA and RNA that provides the basis for the genetic code is a nitrogenous ___________

Base

The ____________ is the site where the repressor binds to turn transcription of the structural genes off.

operator

RNA polymerase binds to the ________ region of the DNA in order to initiate transcription.

promoter

Which type of RNA composes ribosomal subunits together with protein?

rRNA

____ and proteins compose ribosome units.

rRNA

The pieces of DNA produced by restriction endonucleases are termed _____________ ___________

restriction fragments

During _______ DNA replication, the newly made double helices are composed of one strand from the parent template and one newly synthesized strand.

semiconservative

Deoxyribose is the:

sugar in DNA

A _____________ is a discrete cellular structure composed of a neatly packaged DNA molecule.

Chromosome

There are hundreds of different restriction enzymes that each cut ________ at a different palindrome sequence

DNA

Taq polymerase is a _________

DNA polymerase

What enzyme builds the new DNA strands in PCR?

DNA polymerase

Cellular genomes are composed of __________ whereas viral genomes may be either DNA or _____________

DNA;RNA

RNA polymerase converts ________ into the various types of __________

DNA;RNA

Regulatory RNAs

Determine gene expression in prokaryotes and eukaryotes

True or false: bacterial conjugation is sexual reproduction

False

True or false: the chromosomal origin of replication is GC-rich to maintain its double-stranded structure under a wide range of conditions.

False

_______ ________ is a laboratory technique for separating DNA fragments according to length by employing electricity to force the DNA through a gel-like matrix

Gel Electrophoresis

_______ are segments of DNA that contain information used to synthesize groups of related proteins.

Genes

The science of heredity is: -biology -reproduction -genetics

Genetics

Which term represents all of the genetic information within a cell? -Gene -Chromosome -Genome

Genome

The ________ is the genetic makeup of an organism that is ultimately responsible for an organism's expressed characteristics.

Genotype

What is used in the laboratory to separate strands of DNA?

Heat

A sequence of DNA in a eukaryotic gene that does not code for proteins is called a(n)________

Intron

Primer RNA

Laid down in replication as a template for DNA sequence

The enzyme required to seal the sticky ends of DNA pieces after splicing is called ________

Ligase

Bacterial chromosomes are ___________

Located in the nucleoid region of the cytoplasm

What amino acid sequence is encoded by the DNA template sequence 3'-TACCGCGCTCTACCG-'5

Methinonine-Alanine-Arginine-Aspartic acid- Glycine

A(n) _____________ is a permanent inheritable alteration in the DNA sequence of a cell.

Mutation

Chromosomes are located in the _________ of protozoal and fungal cells.

Nucleus

E.coli and other bacteria typically have _________ chromosome(s).

One

A(n) _________ in bacteria consists of regulatory gene, a control region, and structural genes.

Operon

The process of bacteria turning on or off a group of genes that changes its phenotype is called ________ ________

Phase variation

The expressed characteristics resulting from the interaction of the particular genetic make up of an organsim and the environment is the ____________ of that organism.

Phenotype

A(n) _______ mutation involves any substitution of a single nucleotide that does not change the DNA reading frame.

Point

The ________ is the site in an operon where RNA polymerase binds to initiate transcription of the structural genes.

Promoter

What organic molecule is formed from chains of amino acids that are produced in translation?

Protein

In the central theme of molecular biology, DNA encodes _________ which encodes protein.

RNA

_________ _______ is the enzyme that transcribes DNA into RNA.

RNA polymerase

What enzyme cleaves specific locations on DNA and is used to splice genes in genetic engineering?

Restriction endonuclease

__________ __________ is the enzyme that can convert RNA into DNA

Reverse Transcriptase

Two subunits of the ________ compose the site of protein synthesis.

Ribosome

The process of transcription ______ results in the release of a completed RNA transcript

Termination

The expression of the genotype creates traits referred to as:

The Phenotype

What is recombinant DNA technology?

The deliberate modification of genetic structure of an organism to create novel products or organisms

___________ is the process of decoding the messenger RNA into a polypeptide.

Translation

Unlike DNA, RNA contains the nitrogenous base ________

Uracil

What nitrogenous base is found in RNA but not found in DNA?

Uracil

A genetic element such as a plasmid or a bacteriophage that is used to introduce genetic material into a cloning host during recombinant DNA experiments is called a:

Vector

In eukaryotic genes, introns are interspersed between coding regions called __________, that will be translated into protein.

exons

True or false: Gel electrophoresis patterns are the same in different individuals of the same species

false

What is the importance of PCR?

increases the amount of DNA in a sample

Which type of RNA is a copy of the DNA template corresponding to a protein-encoding gene?

mRNA

The spliceosome is comprised of

- RNA -Protein

What nitrogenous bases is found in both DNA and RNA?

- Adenine

The process of eukaryotic transcripts:

- The gene is transcribed to mRNA -A series of adenosines is added to the mRNA -A spliceosome excises introns from the mRNA -The mRNA leaves the nucleus -The mRNA is translated into protein

What are events of translation elongation?

-Amino acids are joined by peptide bonds -The ribosome shifts from one codon on the mRNA to the next -A tRNA delivers the next amino acid in the sequence

what are true for repressible operons?

-Code for anabolic enzymes -Usually turned on unless product is in excess

What are true for inducible operons?

-Code for catabolic enzymes -Usually turned off unless substrate is present -Example is the lac operon

The enzymes the function in DNA replication

-DNA polymerase -Ligase -Helicase

The 3 basic steps in order for PCR?

-Denaturation -Priming -Extension

What two components of a nucleotide are bound to form the backbone of a DNA strand?

-Deoxyribose sugar -Phosphate

The steps in excision repair

-Enzymes recognize a mismatch in the two DNA strands -Enzymes remove the nitrogenous base on one strand -DNA polymerase 1 synthesizes new DNA as needed -Ligase seals the phosphate backbone of the DNA

The process of naming for restriction enzymes

-First letter of bacterial genus -First 2 letters of bacterial species -The order discovered in the bacterium

What are the 3 major types of RNA

-Messenger -Ribosomal -Transfer

What are the 3 components of a DNA nucleotide?

-Nitrogenous base -Phosphate -Deoxyribose sugar

What makes good cloning vectors?

-Plasmids -Bacteriophages

How does RNA differ from DNA in bacteria and eukaryotes?

-RNA is a single- stranded -In RNA, Uracil replaces thymine

The general steps in order for the Recombinant DNA procedure

-Remove and isolate a selected gene from a donor organism -Insert the gene of interest into a vector -Use vector to deliver selected gene into cloning host.

What is commonly shared between bacteria through the process of conjugation?

-Resistance plasmids -Genes for Virulence factors

What events initiate translation?

-Ribosome scans to find AUG on the mRNA transcript -Assembly of the ribosomal subunits

________ mutations occur when errors are made in DNA replication whereas _________ are caused by exposure to radiation or chemical agents.

-Spontaneous -Induced

What strategies are used to isolate a target gene for use in recombinant DNA technology?

-Synthesis of cDNA -Amplification by PCR -Gene probing for desired sequences -Digestion with endonucleases

A codon contains how many nucleotides?

3

Which template DNA sequence encodes the peptide sequence Phenylalanine-leucine-aspartic acid-valine?

3'-AAAAACCTACAT-5'

If a DNA molecule contains 15% adenine nucleotides, what percent of cytosine does it contain?

35%

what is the complementary DNA sequence to the DNA template 3'-ATACTAAAATTT-5'?

5'-TATGATTTTAAA-3'

The genes of which microorganism(s) are arranged as operons?

Bacteria

What is used in the laboratory to renature DNA into its normal double stranded for?

Cooling

In the bacterium Escherichia coli, where is the chromosome located?

Cytoplasm

Transcription occurs in the ________ of bacteria and the _______ of yeast cells.

Cytoplasm; Nucleus

Genomes of cells are composed of ______________

DNA

During transcription, RNA polymerase synthesizes ________ from a(n) _________ template.

RNA; DNA

The primary intent of _______ DNA technology is to combine the genetic material from two organisms

Recombinant

What refers to the transfer of genes between donor and recipient microorganisms?

Recombination

Ribozymes

Remove introns in eukaryotes

DNA _________ must occur prior to cell division to ensure that each new cell has a complete set of DNA chromosome(s)

Replication

A _________ mutation alters the DNA sequence of a gene, but does not change the amino acid sequence of the protein that is encoded by the gene.

Silent

The mRNA squence AUG, specifying the first amino acid in protein sequences, is called the ________ codon

Start

_______ genes code for proteins

Structural

What is a cloning host?

The organism that receives and replicates a foreign piece of DNA inserted during a genetic engineering experiment

All DNA nucleotides contain:

The same sugar and phosphate, but different nitrogenous bases

________ and _________ of the foreign gene to make the protein product will occur if a cloning host receives the recombinant plasmid.

Transcription;Translation

Which type of horizontal gene transfer has been linked to the virulence of bacteria such as Clostridium, Streptococcus pyogenes, and Corynebacterium diphtheriae?

Transduction

_______ involves the transfer of DNA via bacteriophages.

Transduction

Vertical gene transfer

Transfer of DNA from a parent organisms during reproduction

Horizontal gene transfer

Transfer of DNA from a source other than the parent organisms

If a microbiologist wanted to insert a human gene into a bacterial cell, which type of horizontal gene transfer would be a useful means of accomplishing this goal?

Transformation

Which gene transfer method involves the uptake of free DNA by competent bacterial cells?

Transformation

tRNA carries ________ _________ to the ribosome during protein synthesis.

amino acids

Most plasmid vectors contain an _________ ________ gene as well as the gene of interest.

antibiotic resistance

The first challenge in gene __________, or recombinant DNA technology, is locating and isolating a target gene.

cloning

According to the rules of complementary base pairing, the nitrogenous base ______ forms hydrogen bonds with guanine.

cytosine