Biotechnology, Recombinant DNA, and Applied Immunology

Vocabulary practice flashcards covering tools, techniques, and diagnostic applications in biotechnology, recombinant DNA technology, and immunology based on Microbiology: An Introduction (13th Edition) Chapters 9 and 18.

Biotechnology

The industrial or commercial use of microorganisms, cells, or cell components to synthesize practical products such as foods, antibiotics, vitamins, and enzymes.

Recombinant DNA (rDNA) Technology

Techniques involving the insertion or alteration of genes within an organism's genome to synthesize desired protein products.

Vector (Gene Cloning)

A self-replicating DNA molecule, such as a plasmid or viral genome, utilized as a vehicle to transport foreign genetic material into a host cell.

Clone

A population of genetically identical cells that originate from a single ancestral cell, each harboring copies of the recombinant vector.

Restriction Enzymes

Bacterial endonucleases that recognize and cleave specific double-stranded nucleotide sequences; they naturally digest bacteriophage DNA while bacterial DNA is protected by methylated cytosines.

Sticky Ends

Staggered, single-stranded nucleotide overhangs generated by restriction enzyme cleavage that can pair via hydrogen bonds with complementary sequences cut by the same enzyme.

pUC19

A standard circular cloning plasmid vector featuring an origin of replication ($\text{ori}$), an ampicillin resistance marker ($\text{amp}^R$), a $\beta$-galactosidase gene ($\text{lacZ}$), and restriction enzyme cleavage sites for HindIII, BamHI, and EcoRI.

Polymerase Chain Reaction (PCR)

An in vitro enzymatic process for amplifying small quantities of target DNA through repeating cycles of strand separation at $94^\circ\text{C}$, primer annealing at $60^\circ\text{C}$, and DNA polymerase extension at $72^\circ\text{C}$.

Reverse-Transcription PCR (RT-PCR)

A variation of PCR that uses cellular mRNA as the initial template to synthesize complementary DNA via reverse transcriptase before standard amplification.

Transformation

The mechanism of genetic alteration in which competent cells take up naked foreign DNA directly from the surrounding medium.

Electroporation

A laboratory method that utilizes brief pulses of an electrical current to induce microscopic pores in cell membranes, facilitating the entry of foreign DNA.

Protoplast Fusion

A technique for genetic recombination in which bacterial or plant cell walls are enzymatically stripped to form protoplasts, which are subsequently treated with polyethylene glycol to induce fusion and chromosome exchange.

Microinjection

A mechanical procedure that introduces foreign DNA directly into a target cell, such as an egg immobilized by a holding suction pipette, using a glass micropipette with a tip diameter smaller than the cell.

Complementary DNA (cDNA)

Artificial DNA synthesized in vitro from mature eukaryotic mRNA by reverse transcriptase; it contains only protein-coding exons and lacks noncoding introns.

Blue-White Screening

A selection method on medium containing ampicillin and X-gal where non-recombinant bacteria hydrolyze X-gal to form blue colonies, whereas recombinant bacteria with foreign DNA inserted into the $\text{lacZ}$ gene remain white.

Ti Plasmid

A tumor-inducing plasmid derived from Agrobacterium tumefaciens that is genetically engineered to insert foreign genes located on its T-DNA region into a recipient plant chromosome.

Southern Blotting

A molecular diagnostic technique in which DNA fragments separated by agarose gel electrophoresis are blotted onto a nitrocellulose membrane and detected using sequence-specific labeled probes.

Restriction Fragment Length Polymorphisms (RFLPs)

Distinct variations in the lengths of DNA fragments generated when specific restriction endonucleases cleave genomic DNA samples, used in genetic fingerprinting and disease screening.

Bioinformatics

The scientific discipline focused on collecting, organizing, and analyzing genomic and genetic sequence data using computer-assisted and computational methods.

Proteomics

The systematic, large-scale study and structural determination of all expressed cellular proteins and their functional interactions.

Variolation

An early method of immunization where material taken from smallpox pustules was inoculated into the skin of healthy recipients to induce a mild, protective infection.

Vaccine

A biological preparation consisting of whole killed organisms, living attenuated pathogens, or antigenic fractions administered to stimulate active adaptive immunity.

Herd Immunity

A state of communal resistance against an infectious disease achieved when a high proportion of the population is immune, limiting the spread of the pathogen to non-immune individuals.

Live Attenuated Vaccines

Immunizing preparations composed of living microbes whose virulence has been weakened; they mimic natural infection and induce long-lasting humoral and cellular immunity without boosters.

Inactivated Killed Vaccines

Vaccines containing intact pathogens killed by chemical or heat treatment; they primarily stimulate humoral immunity and require repeated booster injections to maintain protection.

Subunit Vaccines

Vaccines formulated using only specific antigenic fragments of a microorganism rather than whole pathogens, reducing undesirable side effects.

Toxoids

Bacterial exotoxins treated chemically to destroy toxicity while preserving the antigenic structure necessary to elicit neutralizing antitoxin antibodies.

Virus-Like Particle (VLP) Vaccines

Non-infectious vaccine formulations assembled from viral capsid proteins that structurally mimic native viral envelopes but completely lack viral genetic material.

Conjugated Vaccines

Vaccines that enhance immunogenicity in young children by chemically attaching poorly antigenic capsular polysaccharides to proteins such as diphtheria or tetanus toxoid.

Nucleic Acid (DNA) Vaccines

Vaccines composed of recombinant naked plasmid DNA injected into muscle tissue, causing host cells to synthesize the encoded protein antigen and elicit both humoral and cellular responses.

Adjuvants

Chemical additives included in vaccine preparations, such as alums and monophosphoryl lipid A in the United States, that enhance the innate immune response and improve vaccine efficacy.

Sensitivity (Diagnostic Immunology)

The probability that an immunological diagnostic test will show a reactive result when evaluating a true-positive specimen.

Specificity (Diagnostic Immunology)

The probability that an immunological diagnostic test will not show a false-positive reaction when analyzing a true-negative specimen.

Direct Agglutination Test

A serological assay in which antibodies react directly with large particulate antigens, such as whole bacteria or red blood cells, forming visible macroscopic clumps.

Antibody Titer

The concentration of circulating serum antibodies quantified as the reciprocal of the greatest serum dilution (e.g., $160$ for a $1:160$ dilution) that produces a discernible positive agglutination reaction.

Indirect (Passive) Agglutination Test

An agglutination reaction where soluble antigens or antibodies are adsorbed onto artificial carrier particles (such as microscopic latex beads) to make the reaction visible as aggregate clumping.

Hemagglutination

The aggregation or clumping of red blood cells caused by specific binding between erythrocyte surface antigens and complementary antibodies, standardly applied in ABO blood typing.

Viral Hemagglutination

The clumping of erythrocytes mediated directly by surface components of certain viruses (including mumps, measles, and influenza) without an antigen-antibody reaction.

Fluorescence-Activated Cell Sorter (FACS)

A specialized flow cytometer that focuses cells in individual droplets, measures cell fluorescence and scatter via laser excitation, imparts an electric charge to selected cells, and sorts them into separate tubes.

Direct ELISA

An enzyme-linked immunosorbent assay that identifies antigens by immobilizing antibodies onto a microtiter well, adding the patient sample, and sandwiching bound antigen with enzyme-labeled specific antibodies that produce a colored product upon substrate addition.

Indirect ELISA

An enzyme-linked immunosorbent assay designed to detect specific antibodies in patient serum by incubating it in an antigen-coated well and revealing bound antibody using enzyme-linked anti-human globulin antibodies.

Monoclonal Antibody Pregnancy Test

A rapid immunochromatographic test strip in which free monoclonal antibodies and fixed capture antibodies form a sandwich complex with human chorionic gonadotropin ($\text{hCG}$), generating a visible color line.

Hybridoma

A fused cell created by combining an antibody-producing B lymphocyte from an immunized mouse spleen with an immortal myeloma cell, cultured in selective medium to yield monoclonal antibodies.

Western Blotting (Immunoblotting)

A diagnostic method used to identify specific proteins in complex mixtures by separating them according to molecular weight via gel electrophoresis, transferring them to a membrane filter, and probing with tagged antibodies.