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Full-Text Articles in Organisms

Whole Genome Sequence Data Implicate Rbfox1 In Epilepsy Risk In Baboons, Mark Z. Kos, Melanie A. Carless, Lucy Blondell, Mary M. Leland, Koyle D. Knape, Harald H. H. Goring, Charles A. Szabo Sep 2023

Whole Genome Sequence Data Implicate Rbfox1 In Epilepsy Risk In Baboons, Mark Z. Kos, Melanie A. Carless, Lucy Blondell, Mary M. Leland, Koyle D. Knape, Harald H. H. Goring, Charles A. Szabo

Research Symposium

Background: Baboons exhibit a genetic generalized epilepsy (GGE) that resembles juvenile myoclonic epilepsy and may represent a suitable genetic model for human epilepsy. The genetic underpinnings of epilepsy were investigated in a baboon colony at the Southwest National Primate Research Center (San Antonio, TX) through the analysis of whole-genome sequence (WGS) data.

Methods: Baboon WGS data were obtained for 38 cases and 19 healthy controls from the NCBI Sequence Read Archive and, after standard QC filtering, two subsets of variants were examined: (1) 20,881 SNPs from baboon homologs of 19 candidate GGE genes; and (2) 36,169 protein-altering SNPs. Association tests …


A Dna-Peptide Crosslink (Dpc) Increases Mutagenicity In Sos-Induced Escherichia Coli, Alessandra Bassani May 2023

A Dna-Peptide Crosslink (Dpc) Increases Mutagenicity In Sos-Induced Escherichia Coli, Alessandra Bassani

Honors Scholar Theses

Bacteria, such as Escherichia coli, have an inducible system in response to DNA damage termed the SOS response. This system is activated when the replicative DNA polymerase (Pol) III encounters a lesion, uncouples from DNA helicase, and single-stranded DNA (ssDNA) accumulates at the replication fork. In this study, we investigated DNA-peptide crosslink (DpC), a common lesion that results from cross-linking of proteins or peptides, UV irradiation, and alkylating agents. To increase survival following formation of a lesion, the SOS response can utilize homologous recombination, translesion synthesis (TLS), or excision repair. With TLS, the levels of DNA Pol II, IV, …


The Presence Of Tetracycline-Resistant Bacteria In A Kean University Campus Soil Sample, Esther Blankson, Jessica Kobilas, Gianna Medeiros Apr 2023

The Presence Of Tetracycline-Resistant Bacteria In A Kean University Campus Soil Sample, Esther Blankson, Jessica Kobilas, Gianna Medeiros

Kean Quest

The spread of antimicrobial resistance (AMR) in the environment is a worldwide problem that threatens human health. Bacteria are becoming increasingly resistant to antibiotics as the consumption of antibiotics grows. In particular, soil can be contaminated with bacteria that are resistant to antibiotics. As of today, there is no surveillance system that tracks the spread of antibiotic-resistant bacteria, however, Tufts University aims to change this by implementing the Prevalence of Antibiotic Resistance in the Environment (PARE) project. The course-based PARE project consists of research students sampling soil in diverse locations and reporting the prevalence of antibiotic-resistant bacteria. The purpose of …


Knockout Of Endospanin 1 Via Crispr In Zebrafish, Danio Rerio, Jared Kittinger Jan 2023

Knockout Of Endospanin 1 Via Crispr In Zebrafish, Danio Rerio, Jared Kittinger

Williams Honors College, Honors Research Projects

I made endospanin 1 knockout (KO) zebrafish to examine its effects on lipid and bone metabolism. Endospanin 1, or leptin receptor overlapping transcript (leprot), is a cytosolic protein linked to the protein hormone leptin that influences the trafficking of leptin receptors to the plasma membrane of cells. Genes for endospanin and tyrosinase (a pigmentation enzyme) were targeted via a microinjection of guide RNAs and CRISPR Cas9 into zebrafish embryos at 2-4 cell stages. I was able to disrupt the endospanin 1 gene (based upon the disruption of tyrosinase), but very few mutant zebrafish fully developed into adults. Only low KO …


Alzheimer’S Disease Genetics And Short-Chain Fatty Acid Treatment In Studies Of The Murine Gut Microbiome, Diana Zajac Jan 2023

Alzheimer’S Disease Genetics And Short-Chain Fatty Acid Treatment In Studies Of The Murine Gut Microbiome, Diana Zajac

Theses and Dissertations--Physiology

Elucidating the relationship of the gut microbiome in Alzheimer's Disease (AD) risk and pathogenesis is an area of intense interest. Since 60 to 80% of AD risk is related to genetics and APOE alleles represent the most impactful genetic risk factors for AD, their mechanism(s) of action are under intense scrutiny.

First, I conducted a study on APOE targeted replacement mice to investigate the impact of APOE alleles on the murine gut microbiome. The relative abundance of bacteria from the family Ruminococacceae and related genera increased with APOE2 status. The relative abundance of the class Erysipelotrichia increased with APOE4 status, …


Resolving The Repression Pathway Of Virulence Gene Hila In Salmonella, Alexandra King, Lon Chubiz Phd, Brenda Pratte, Lauren Daugherty Jun 2022

Resolving The Repression Pathway Of Virulence Gene Hila In Salmonella, Alexandra King, Lon Chubiz Phd, Brenda Pratte, Lauren Daugherty

Undergraduate Research Symposium

Salmonella is a relatively abundant, virulent species of bacteria that is most known for spreading gastrointestinal diseases through food. These illnesses result in approximately 1.35 million infections, including over 25,000 hospitalizations each year, in the U.S. alone (CDC.gov). As antibiotic resistance becomes an increasingly urgent public health problem, the importance of developing alternative treatment methods is only becoming more crucial. One of the genes responsible for this virulence is known as hilA. HilA is the main transcriptional regulator of Salmonella Pathogenicity Island-1 gene (UniProt). SPI-1 plays an important role in the invasion of Salmonella into epithelial cells. The proteins encoded …


Assesment Of Antibiotic Resistant Gene Expression In Clinical Isolates Of Pseudomonas Aeruginosa, Dustin Esmond Sep 2021

Assesment Of Antibiotic Resistant Gene Expression In Clinical Isolates Of Pseudomonas Aeruginosa, Dustin Esmond

Biology Theses

Increasing prevalence of nosocomial infections by antimicrobial resistant pathogens resulting in higher mortality rates and financial burden is of great concern. Pseudomonas aeruginosa represents one of six highly virulent “ESKAPE” pathogens that exhibit considerable intrinsic drug resistance as well as mechanisms for acquiring further resistance. As many of these mechanisms are regulated through gene expression, we sought to identify regulatory strategies and patterns at play in 23 clinical isolates collected from Baku, Azerbaijan and Tyler, Texas, USA. Real-time quantitative polymerase chain reaction was performed on six gene targets implicated in resistance and contrasted with antibiotic phenotypes. We found AmpC cephalosporinase …


Wild Mice With Different Social Network Sizes Vary In Brain Gene Expression, Patricia C. Lopes, Barbara König Jul 2020

Wild Mice With Different Social Network Sizes Vary In Brain Gene Expression, Patricia C. Lopes, Barbara König

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Background

Appropriate social interactions influence animal fitness by impacting several processes, such as mating, territory defense, and offspring care. Many studies shedding light on the neurobiological underpinnings of social behavior have focused on nonapeptides (vasopressin, oxytocin, and homologues) and on sexual or parent-offspring interactions. Furthermore, animals have been studied under artificial laboratory conditions, where the consequences of behavioral responses may not be as critical as when expressed under natural environments, therefore obscuring certain physiological responses. We used automated recording of social interactions of wild house mice outside of the breeding season to detect individuals at both tails of a distribution …


The Role Of Manganese In Streptococcus Sanguinis, Tanya M. Puccio Jan 2020

The Role Of Manganese In Streptococcus Sanguinis, Tanya M. Puccio

Theses and Dissertations

Streptococcus sanguinis is primarily associated with oral health as a commensal bacterium. As an opportunistic pathogen, S. sanguinis is capable of colonizing heart valve vegetations, leading to the disease infective endocarditis. Previous studies from our lab have identified the high-affinity manganese transporter SsaACB as important for endocarditis virulence. The impact that manganese depletion has on S. sanguinis had never been evaluated and a secondary manganese transporter has not been identified. Thus, we employed the use of a fermentor to control large-scale growth over time and depleted manganese in an ΔssaACB mutant using a metal chelator, EDTA. The changes in …


Crispr/Cas9 In Yeast: A Multi-Week Laboratory Exercise For Undergraduate Students, Randi J. Ulbricht May 2019

Crispr/Cas9 In Yeast: A Multi-Week Laboratory Exercise For Undergraduate Students, Randi J. Ulbricht

Open Educational Resources

Providing undergraduate life-science students with a course-based research experience that utilizes cutting-edge technology, is tractable for students, and is manageable as an instructor is a challenge. Here, I describe a multi-week lesson plan for a laboratory-based course with the goal of editing the genome of budding yeast, Saccharomyces cerevisiae. Students apply knowledge regarding advanced topics such as: CRISPR/Cas9 gene editing, DNA repair, genetics, and cloning. The lesson requires students to master skills such as bioinformatics analysis, restriction enzyme digestion, ligation, basic microbiology skills, polymerase chain reaction, and plasmid purification. Instructors are led through the technical aspects of the protocols, …


Biotechnological Application In Aquaculture And Its Sustainability Constraints, Olaganathan Rajee, Tang Kar Mun Alicia Jan 2019

Biotechnological Application In Aquaculture And Its Sustainability Constraints, Olaganathan Rajee, Tang Kar Mun Alicia

Publications

The valuable nutritional and biochemical properties have made fisheries products one of the most vital high-quality protein sources for human consumption. Aquaculture has become the great alternative to substitute wild catches when the yield from fishing are no longer sufficient to sustain the massive food demand of the human population which is constantly burgeoning. However, aquaculture requires multidisciplinary approaches with holistic and environmental-friendly management measures to ensure its long term success and sustainability. Biotechnological applications have enhanced the effectiveness and cost-efficiencies of aquaculture by augmenting the productivity of aquaculture to meet global needs. Despite the benefits, the biotechnological application in …


Clpxp-Regulated Proteins Suppress Requirement For Reca In Dam Mutants Of Escherichia Coli K-12, Amie Savakis Oct 2018

Clpxp-Regulated Proteins Suppress Requirement For Reca In Dam Mutants Of Escherichia Coli K-12, Amie Savakis

Masters Theses

Double strand breaks (DSB) are a common source of DNA damage in both prokaryotes and eukaryotes. If they are not repaired or are repaired incorrectly, they can lead to cell death (bacteria) or cancer (humans). In Escherichia coli, repair of DSB are typically accomplished via homologous recombination and mediated by RecA. This repair pathway, among others, is associated with activation of the SOS response. DNA adenine methyltransferase (dam) mutants have an increased number of DSB and, therefore, are notorious for being RecA-dependent for viability. Here, we show that the synthetic lethality of Δdam/ΔrecA is suppressed when clpP is removed, suggesting …


Studies Of Norspermidine Uptake In Drosophila Suggest The Existence Of Multiple Polyamine Transport Pathways, Michael Dieffenbach Jan 2018

Studies Of Norspermidine Uptake In Drosophila Suggest The Existence Of Multiple Polyamine Transport Pathways, Michael Dieffenbach

Honors Undergraduate Theses

Polyamines are a class of essential nutrients involved in many basic cellular processes such as gene expression, cell proliferation, and apoptosis. Without polyamines, cell growth is delayed or halted. Cancerous cells require an abundance of polyamines through a combination of synthesis and transport from the extracellular environment. An FDA-approved drug, D,L-α-difluoromethylornithine (DFMO), blocks polyamine synthesis but is ineffective at inhibiting cell growth due to polyamine transport. Thus, there is a need to develop drugs that inhibit polyamine transport to use in combination with DFMO. Surprisingly, little is known about the polyamine transport system in humans and other eukaryotes. Understanding the …


Genetic Signatures For Helicobacter Pylori Strains Of West African Origin, Kennady K. Bullock, Carrie L. Shaffer, Andrew W. Brooks, Ousman Secka, Mark H. Forsyth, Mark S. Mcclain, Timothy L. Cover Nov 2017

Genetic Signatures For Helicobacter Pylori Strains Of West African Origin, Kennady K. Bullock, Carrie L. Shaffer, Andrew W. Brooks, Ousman Secka, Mark H. Forsyth, Mark S. Mcclain, Timothy L. Cover

Veterinary Science Faculty Publications

Helicobacter pylori is a genetically diverse bacterial species that colonizes the stomach in about half of the human population. Most persons colonized by H. pylori remain asymptomatic, but the presence of this organism is a risk factor for gastric cancer. Multiple populations and subpopulations of H. pylori with distinct geographic distributions are recognized. Genetic differences among these populations might be a factor underlying geographic variation in gastric cancer incidence. Relatively little is known about the genomic features of African H. pylori strains compared to other populations of strains. In this study, we first analyzed the genomes of …


Complete Genome Sequence Of Spiroplasma Turonicum Tab4ct, A Bacterium Isolated From Horse Flies (Haematopota Sp.), Wen-Sui Lo, Gail E. Gasparich, Chih-Horng Kuo Sep 2016

Complete Genome Sequence Of Spiroplasma Turonicum Tab4ct, A Bacterium Isolated From Horse Flies (Haematopota Sp.), Wen-Sui Lo, Gail E. Gasparich, Chih-Horng Kuo

Gail Gasparich

Spiroplasma turonicum Tab4cT was isolated from a horse fly (Haematopota sp.; probably Haematopota pluvialis) collected at Champchevrier, Indre-et-Loire, Touraine, France, in 1991. Here, we report the complete genome sequence of this bacterium to facilitate the investigation of its biology and the comparative genomics among Spiroplasma spp.


Optimization Of A Genomic Editing System Using Crispr/Cas9-Induced Site-Specific Gene Integration, Jillian L. Mccool Ms., Nick Hum, Gabriela G. Loots Aug 2016

Optimization Of A Genomic Editing System Using Crispr/Cas9-Induced Site-Specific Gene Integration, Jillian L. Mccool Ms., Nick Hum, Gabriela G. Loots

STAR Program Research Presentations

The CRISPR-Cas system is an adaptive immune system found in bacteria which helps protect against the invasion of other microorganisms. This system induces double stranded breaks at precise genomic loci (1) in which repairs are initiated and insertions of a target are completed in the process. This mechanism can be used in eukaryotic cells in combination with sgRNAs (1) as a tool for genome editing. By using this CRISPR-Cas system, in addition to the “safe harbor locus,” ROSAβ26, the incorporation of a target gene into a site that is not susceptible to gene silencing effects can be achieved through few …


Genetic Analysis Reveals A Hierarchy Of Interactions Between Polycystin-Encoding Genes And Genes Controlling Cilia Function During Left-Right Determination, Daniel T. Grimes, Jennifer L. Keynton, Maria T. Buenavista, Xingjian Jin, Saloni H. Patel, Shinohara Kyosuke, Jennifer Vibert, Debbie J. Williams, Hiroshi Hamada, Rohana Hussain, Surya M. Nauli, Dominic P. Norris Jun 2016

Genetic Analysis Reveals A Hierarchy Of Interactions Between Polycystin-Encoding Genes And Genes Controlling Cilia Function During Left-Right Determination, Daniel T. Grimes, Jennifer L. Keynton, Maria T. Buenavista, Xingjian Jin, Saloni H. Patel, Shinohara Kyosuke, Jennifer Vibert, Debbie J. Williams, Hiroshi Hamada, Rohana Hussain, Surya M. Nauli, Dominic P. Norris

Pharmacy Faculty Articles and Research

During mammalian development, left-right (L-R) asymmetry is established by a cilia-driven leftward fluid flow within a midline embryonic cavity called the node. This ‘nodal flow’ is detected by peripherally-located crown cells that each assemble a primary cilium which contain the putative Ca2+ channel PKD2. The interaction of flow and crown cell cilia promotes left side-specific expression of Nodal in the lateral plate mesoderm (LPM). Whilst the PKD2-interacting protein PKD1L1 has also been implicated in L-R patterning, the underlying mechanism by which flow is detected and the genetic relationship between Polycystin function and asymmetric gene expression remains unknown. Here, we …


Non-Essentiality Of Alr And Muri Genes In Mycobacteria, Philion L. Hoff, Denise Zinniel, Raúl G. Barletta Apr 2016

Non-Essentiality Of Alr And Muri Genes In Mycobacteria, Philion L. Hoff, Denise Zinniel, Raúl G. Barletta

UCARE Research Products

Amino acids are the building blocks of life. If DNA is the blueprint, amino acids are the lumber that proteins are built with. Proteins are built with left-handed, L- forms of amino acids. Bacteria have an essential cell wall component that happens to be an exception: peptidoglycan. Bacteria have enzymes called racemases that convert L- amino acid forms into right-handed, D- forms. Amino acids participate in many reactions with keto acids. Transaminases allow conversion between amino acids by transfer of an amino group.

Previous reports claimed there is no D-ala transaminase activity in mycobacteria and thus alr and murI genes …


Mechanisms Of Adaptation In The Newly Invasive Species Brachypodium Sylvaticum (Hudson) Beauv., Gina Lola Marchini Dec 2015

Mechanisms Of Adaptation In The Newly Invasive Species Brachypodium Sylvaticum (Hudson) Beauv., Gina Lola Marchini

Dissertations and Theses

It is common knowledge that invasive species cause worldwide ecological and economic damage, and are nearly impossible to eradicate. However, upon introduction to a novel environment, alien species should be the underdogs: They are present in small numbers, possess low genetic diversity, and have not adapted to the climate and competitors present in the new habitat. So, how are alien species able to invade an environment occupied by native species that have already adapted to the local environment? To discover some answers to this apparent paradox I conducted four ecological genetic studies that utilized the invasive species Brachypodium sylvaticum (Hudson) …


Proof-Of-Concept Of Environmental Dna Tools For Atlantic Sturgeon Management, Jameson Hinkle Jan 2015

Proof-Of-Concept Of Environmental Dna Tools For Atlantic Sturgeon Management, Jameson Hinkle

Theses and Dissertations

Abstract

The Atlantic Sturgeon (Acipenser oxyrinchus oxyrinchus, Mitchell) is an anadromous species that spawns in tidal freshwater rivers from Canada to Florida. Overfishing, river sedimentation and alteration of the river bottom have decreased Atlantic Sturgeon populations, and NOAA lists the species as endangered. Ecologists sometimes find it difficult to locate individuals of a species that is rare, endangered or invasive. The need for methods less invasive that can create more resolution of cryptic species presence is necessary. Environmental DNA (eDNA) is a non-invasive means of detecting rare, endangered, or invasive species by isolating nuclear or mitochondrial DNA (mtDNA) from the …


Characterization Of Staphylococcus Aureus Lipase, Vithooshan Vijayakumaran Aug 2013

Characterization Of Staphylococcus Aureus Lipase, Vithooshan Vijayakumaran

Electronic Thesis and Dissertation Repository

USA300, a strain of community-associated methicillin resistant Staphylococcus aureus (CA-MRSA), has become prevalent in the community. Colonization of human skin requires mechanisms that allow this bacterium to overcome the innate immune defenses on the skin, including secretion of antimicrobial lipids. Antimicrobial lipids inhibit S. aureus growth and induce the staphylococcal proteolytic cascade, producing aureolysin (Aur) which processes the lipase glycerol ester hydrolase (Geh). Nearly all S. aureus strains secrete Geh, yet little information exists concerning its function. Using purified Aur and Geh we confirm that aureolysin processes proGeh to Geh. We then confirmed that geh was required for lipase activity …


High-Throughput Genome Sequencing Of Lichenizing Fungi To Assess Gene Loss In The Ammonium Transporter/Ammonia Permease Gene Family, Tami R. Mcdonald, Olaf Mueller, Fred S. Dietrich, François Lutzoni Dec 2012

High-Throughput Genome Sequencing Of Lichenizing Fungi To Assess Gene Loss In The Ammonium Transporter/Ammonia Permease Gene Family, Tami R. Mcdonald, Olaf Mueller, Fred S. Dietrich, François Lutzoni

Tami McDonald

No abstract provided.


Development Of Pyrf-Based Genetic System For Targeted Gene Deletion In Clostridium Thermocellum And Creation Of A Pta Mutant, Shital A. Tripathi, Daniel G. Olson, D. Aaron Argyros, Bethany B. Miller, Trisha F. Barrett, Daniel M. Murphy, Jesse D. Mccool, Anne K. Warner, Vineet B. Rajgarhia, Lee R. Lynd, David A. Hogsett, Nicky C. Caiazza Aug 2010

Development Of Pyrf-Based Genetic System For Targeted Gene Deletion In Clostridium Thermocellum And Creation Of A Pta Mutant, Shital A. Tripathi, Daniel G. Olson, D. Aaron Argyros, Bethany B. Miller, Trisha F. Barrett, Daniel M. Murphy, Jesse D. Mccool, Anne K. Warner, Vineet B. Rajgarhia, Lee R. Lynd, David A. Hogsett, Nicky C. Caiazza

Dartmouth Scholarship

We report development of a genetic system for making targeted gene knockouts in Clostridium thermocellum, a thermophilic anaerobic bacterium that rapidly solubilizes cellulose. A toxic uracil analog, 5-fluoroorotic acid (5-FOA), was used to select for deletion of the pyrF gene. The ΔpyrF strain is a uracil auxotroph that could be restored to a prototroph via ectopic expression of pyrF from a plasmid, providing a positive genetic selection. Furthermore, 5-FOA was used to select against plasmid-expressed pyrF, creating a negative selection for plasmid loss. This technology was used to delete a gene involved in organic acid production, namely pta, which encodes …


Ewe And Wether Trials - Tools For Benchmarking Your Sheep Genetics, Lock Butler Apr 2006

Ewe And Wether Trials - Tools For Benchmarking Your Sheep Genetics, Lock Butler

Bulletins 4000 -

Research and sheep productivity trial results demonstrate a huge variability in genetic productivity between flocks. For example a range of up to 2 kg clean fleece weight, 5 microns, 55 percentage points in lambing percentage and 20 kg live weight, can lead to big differences in gross margin between flocks.

There is an opportunity for genetic improvement, depending on your current ram source or sires performance. For example, Western Australian (WA) Wether Trial results suggest half the WA flocks could improve clean fleece weight per head by half a kilogram or more. The trial results suggest that this could occur …


Whole Genome Sequencing Of L.Monocytogenes And L.Innocua : A Basis For Comparative Genomics Of The Genus Listeria, Rachel Purcell Jan 2000

Whole Genome Sequencing Of L.Monocytogenes And L.Innocua : A Basis For Comparative Genomics Of The Genus Listeria, Rachel Purcell

Theses

Listeria monocytogenes is a gram-positive, food-borne human and animal pathogen. L.innocua is a non-pathogenic species the most closely related to L. monocytogenes. Comparative genomics between a pathogenic and a closely related non-pathogenic species is a powerful approach for identifying genes or regions on the chromosome, which might be involved in virulence. Therefore whole genome sequencing of these two organisms was undertaken. The strategy used was based on a random approach combined with end-sequencing of a medium insert library for the finishing phase. Based on the available sequence data for these two species an in silico analysis for the presence of …


Methicillin Resistant Staphylococcus Aureus (Mrsa): Molecular Detection And Dna Fingerprinting, Leslie Cotter Jan 1998

Methicillin Resistant Staphylococcus Aureus (Mrsa): Molecular Detection And Dna Fingerprinting, Leslie Cotter

Theses

Throughout the 1990s, the incidence of methicillin-resistant Staphylococcus aureus has increased in many health care areas including acute and chronic care facilities, outpatient clinics and in the community. Once introduced into a health care environment, this nosocomial pathogen can spread rapidly and as MRSA are resistant to multiple antibiotics, treatment is often difficult. Therefore effective infection control measures are required to prevent cross-infection and further spread of endemic strains.

In this study, a sensitive and specific triplex-PCR assay was designed for MRSA detection, wherein three genes, the methicillin resistance gene (mecA). femA and the extracellular thermonuclease gene (rmc) were simultaneously …


Experimentation To Develop Procedures To Be Used In The Investigation Of The Effects Of Restriction On The Unmodified Dna Of The Bacteriophage Lamda, John Haynes Jun 1973

Experimentation To Develop Procedures To Be Used In The Investigation Of The Effects Of Restriction On The Unmodified Dna Of The Bacteriophage Lamda, John Haynes

Honors Theses

The results of experimentation approximately twenty years ago with variuos bacteriophages by Ralston and Krueger16, Anderson and Felix1, Luria and Human12, and by Bertani and Weigle2 have shown that the host range of a given phage depends directly on the bacterial strain on which the phage has last propagated. This event came to be known as host-induced modification or host-controlled variation. As this phage host range is controlled by the host environment and can be altered from one generation to another it has, according to Luria, made microbiology "the last stronghold of Lamarckism" …