Biomedical Engineering and Bioengineering Commons^™

Nanoparticle Treatment To Counter Reactive Oxygen Species After Traumatic Brain Injury, Brandon Mcdonald, Forrest Kievit

UCARE: Research Products

Traumatic brain injury (TBI) is defined as damage to the brain, resulting from an external mechanical force, such as an impact to the head (Kievit et. al, 2016).There are several examples that could result in a potential TBI; such as falling with contact to the head, car accidents and even physical activities including football, wrestling, and boxing. Because of the several different scenarios that an individual could impact their head, TBI’s have become an all too common aspect of everyday life. TBI is currently the leading cause of death and disability in children and adults under the age of 45, …

Biotech Connector Brochure

Biotech Connector

The Biotech Connector represents an important opportunity to serve the economic needs of the people of Nebraska through further diversification of Nebraska's economy, and by helping forge and illuminate a pathway to jobs in the biotechnology space for Nebraska students.

The Biotech Connector is 7,700 sq. ft. of well-equipped wet-lab space located on Nebraska Innovation Campus. We provide incubation space and services to bioscience startups and high-growth biotech and research-based businesses.

Wet lab space provides aspiring startups and technology businesses with access to very expensive laboratory equipment that would be outside of the budget of most startups. Lack of access …

Brassinosteroids Inhibit Autotropic Root Straightening By Modifying Filamentous-Actin Organization And Dynamics, Louise De Bang, Ana Paez-Garcia, Ashley E. Cannon, Sabrina Chin, Jaydeep Kolape, Fuqi Liao, J. Alan Sparks, Qingzhen Jiang, Elison B. Blancaflor

Nebraska Center for Biotechnology: Faculty and Staff Publications

When positioned horizontally, roots grow down toward the direction of gravity. This phenomenon, called gravitropism, is influenced by most of the major plant hormones including brassinosteroids. Epi-brassinolide (eBL) was previously shown to enhance root gravitropism, a phenomenon similar to the response of roots exposed to the actin inhibitor, latrunculin B (LatB). This led us to hypothesize that eBL might enhance root gravitropism through its effects on filamentous-actin (F-actin). This hypothesis was tested by comparing gravitropic responses of maize (Zea mays) roots treated with eBL or LatB. LatB- and eBL-treated roots displayed similar enhanced downward growth compared with controls …

Functional Characterization Of Petiolule-Like Pulvinus (Plp) Gene In Abscission Zone Development In Medicago Truncatula And Its Application To Genetic Improvement Of Alfalfa, Juan Du, Shaoyun Lu, Maofeng Chai, Chuanen Zhou, Liang Sun, Yuhong Tang, Jin Nakashima, Jaydeep Kolape, Zhaozhu Wen, Marjan Behzadirad, Tianxiu Zhong, Juan Sun, Yunwei Zhang, Zeng-Yu Wang

Nebraska Center for Biotechnology: Faculty and Staff Publications

Alfalfa (Medicago sativa L.) is one of the most important forage crops throughout the world. Maximizing leaf retention during the haymaking process is critical for achieving superior hay quality and maintaining biomass yield. Leaf abscission process affects leaf retention. Previous studies have largely focused on the molecular mechanisms of floral organ, pedicel and seed abscission but scarcely touched on leaf and petiole abscission. This study focuses on leaf and petiole abscission in the model legume Medicago truncatula and its closely related commercial species alfalfa. By analysing the petiolule-like pulvinus (plp) mutant in M. truncatula at phenotypic level (breakstrength and …

Enhancing Single Walled Carbon Nanotube Deposition For The Study Of Extracellular Analytes, Joseph A. Stapleton

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Extracellular signaling is a dynamic process responsible for coordinating large scale biological processes. As such, understanding extracellular signaling is important to our determination of normal function and pathophysiological development. High resolution spatial and temporal information are critical to completely understanding these processes. Unfortunately, current methods of detection are lacking in either spatial or temporal resolution of extracellular products, limiting researchers’ ability to understand complex biological processes. A new group of sensors based on fluorescent single walled carbon nanotubes (SWNT) have shown the potential to provide both high quality spatial and temporal resolution for the sensing of analytes. However, while SWNT …

Measuring Impacts Of Uncertainty, Irreversibility, And Loss Aversion On The Adoption Of Crop Canopy Sensors Among Nebraska Corn Producers, Brooks Ronspies

Department of Agricultural Economics: Dissertations, Theses, and Student Research

Understanding barriers to adoption of Precision Agricultural Technologies (PATs) is important to the growth of agricultural productivity, efficiency, and sustainability. This thesis proposes and evaluates a model for estimating the impact of uncertainty, irreversibility, and loss aversion on producers’ adoption of crop canopy sensors in order to explain adoption behavior that contradicts previous expectations about the conditions necessary for technology adoption. The model is evaluated using estimated statistical distributions of price and field characteristics designed to match observations of actual corn and nitrogen prices, and of conventional and crop canopy sensor based nitrogen application. Results from this model using expected …

Design, Development, And Field Testing A Visnir Integrated Multi-Sensing Soil Penetrometer, Nuwan K. Wijewardane

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

The research community in soil science and agriculture lacks a cost-effective and rapid technology for in situ, high resolution vertical soil sensing. Visible and near infra-red (VisNIR) technology has the potential to be used for such sensor development due to its ability to derive multiple soil properties rapidly using a single spectrum. Such efforts must, however, overcome a few challenges: (i) a dry ground soil spectral library that can be used to predict the target soil properties accurately, (ii) a robust design which can acquire high quality VisNIR spectra of soil, (iii) an effective method that can link field intact …

Bioproduction Of Adipic Acid Using Engineered Pseudomonas Putida Kt2440 From Lignin-Derived Aromatics, Howard Willett

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

Current industrial synthesis of adipic acid is nonrenewable and depends on a carcinogenic starting material, benzene. Biocatalysis with an engineered microorganism could turn a renewable feedstock into a value-added chemical such as adipic acid. Here we engineered P. putida KT2440 to transform lignin-derived aromatics, coumarate and ferulate, into adipic acid. Lignin is a recalcitrant plant biopolymer burned for thermal energy. Conversion of lignin into a value-added chemical will improve the efficiency of lignocellulose processing plants. The best performing engineered KT2440 strain produces 2.52 mM adipate at a 9.5% (mole/mole) yield. This was achieved by the genetic insertion of non-natural biosynthetic …

Fibrinogen, Factor Xiii And Fibronectin: A Biophysical And Kinetic Characterization Of Their Interactions, Frank Fabian

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

The development of recombinant-based liquid fibrin tissue sealants having enhanced hemostatic and wound healing properties will involve understanding as yet not well characterized interactions between fibrinogen, fibrin (Fbn) factor XIII, thrombin and fibronectin. We study these phenomena in the context of comparing plasma derived fibrinogen to recombinant fibrinogen (rFI) produced in the milk of transgenic cows. An abundance of purified γγ and γγ’ FI subspecies enables detailed study of γγ or γγ’ biomonomer and their respective Fbn biopolymer formation as having different substrate behaviors of activated plasma derived factor XIII (pFXIIIa₂b₂). High pressure size exclusion (HPSEC) …

Predictive Modeling Of Fate And Transport Of Three Prevalent Contaminants In Midwest Agroecosystem Surface Waters: Nitrate-N, Atrazine, And Escherichia Coli, Samuel Hansen

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

The majority of streams and rivers in the United States (U.S.) are ecologically impaired, or threatened by anthropogenic stressors. Recent reports have found atrazine in drinking water to be associated with increased birth defects and incidences of Non-Hodgkin’s Lymphoma, with higher levels of significance from exposure to both atrazine and nitrate-N. In contrast, recent illnesses from E. coli contaminating vegetables that originated from irrigation water has increased awareness of identifying sources of E. coli entering irrigation reservoirs.

Methods to accurately predict atrazine and E. coli occurrence and potential sources in waterways continue to limit the identifying appropriate and effective prevention …

Bio-Desalination Of Brackish And Seawater Using Halophytic Algae, Endalkachew Sahle-Demessie, Ashraf Aly Hassan, Amro El Badawy

Department of Civil and Environmental Engineering: Faculty Publications

Global demand for water is rising. A sustainable and energy efficient approach is needed to desalinate brackish sources for agricultural and municipal water use. Genetic variation among two algae species, Scenedesmus species (S. sp.) and Chlorella vulgaris (C. vulgaris), in their tolerance and uptake of salt (NaCl) was examined for potential bio-desalination of brackish water. Salt-tolerant hyper-accumulators were evaluated in a batch photobioreactors over salinity concentration ranging from 2 g/L to 20 g/L and different nutrient composition for their growth rate and salt-uptake. During algae growth phase, the doubling time varied between 0.63 and 1.81 days for S …

Advanced Selection Methodologies For Dnazymes In Sensing And Healthcare Applications, Sandeep Kumar, Shikha Jain, Neeraj Dilbaghi, Amrik Singh Ahluwalia, Ashraf Aly Hassan, Ki-Hyun Kim

Department of Civil and Environmental Engineering: Faculty Publications

DNAzymes have been widely explored owing to their excellent catalytic activity in a broad range of applications, notably in sensing and biomedical devices. These newly discovered applications have built high hopes for designing novel catalytic DNAzymes. However, the selection of efficient DNAzymes is a challenging process but one that is of crucial importance. Initially, systemic evolution of ligands by exponential enrichment (SELEX) was a labor-intensive and time-consuming process, but recent advances have accelerated the automated generation of DNAzyme molecules. This review summarizes recent advances in SELEX that improve the affinity and specificity of DNAzymes. The thriving generation of new DNAzymes …

Metabolomics Of Sorghum Roots During Nitrogen Stress Reveals Compromised Metabolic Capacity For Salicylic Acid Biosynthesis, Amy M. Sheflin, Dawn Chiniquy, Chaohui Yuan, Emily Goren, Indrajit Kumar, Max Braud, Thomas Brutnell, Andrea L. Eveland, Susannah Tringe, Peng Liu, Stephen Kresovich, Ellen Marsh, Daniel P. Schachtman, Jessica E. Prenni

Nebraska Center for Biotechnology: Faculty and Staff Publications

Sorghum (Sorghum bicolor [L.] Moench) is the fifth most productive cereal crop worldwide with some hybrids having high biomass yield traits making it promising for sustainable, economical biofuel production. To maximize biofuel feedstock yields, a more complete understanding of metabolic responses to low nitrogen (N) will be useful for incorporation in crop improvement efforts. In this study, 10 diverse sorghum entries (including inbreds and hybrids) were field-grown under low and full N conditions and roots were sampled at two time points for metabolomics and 16S amplicon sequencing. Roots of plants grown under low N showed altered metabolic profiles at …

The Small Rna Teg41 Regulates Expression Of The Alpha Phenol-Soluble Modulins And Is Required For Virulence In Staphylococcus Aureus, Rachel L. Zapf, Richard E. Wiemels, Rebecca A. Keogh, Donald L. Holzschu, Kayla M. Howell, Emily Trzeciak, Andrew R. Caillet, Kellie A. King, Samantha A. Selhorst, Michael J. Naldrett, Jeffrey L. Bose, Ronan K. Carroll

Nebraska Center for Biotechnology: Faculty and Staff Publications

Small RNAs (sRNAs) remain an understudied class of regulatory molecules in bacteria in general and in Gram-positive bacteria in particular. In the major human pathogen Staphylococcus aureus, hundreds of sRNAs have been identified; however, only a few have been characterized in detail. In this study, we investigate the role of the sRNA Teg41 in S. aureus virulence. We demonstrate that Teg41, an sRNA divergently transcribed from the locus that encodes the cytolytic alpha phenolsoluble modulin (αPSM) peptides, plays a critical role in αPSM production. Overproduction of Teg41 leads to an increase in αPSM levels and a corresponding increase in …

Terpene Synthase Genes Originated From Bacteria Through Horizontal Gene Transfer Contribute To Terpenoid Diversity In Fungi, Qidong Jia, Xinlu Chen, Tobias G. Kollner, Jan Rinkel, Jianyu Fu, Jessy Labbe, Wangdan Xiong, Jeroen S. Dickschat, Jonathan Gershenzon, Feng Chen

Nebraska Center for Biotechnology: Faculty and Staff Publications

Fungi are successful eukaryotes of wide distribution. They are known as rich producers of secondary metabolites, especially terpenoids, which are important for fungi-environment interactions. Horizontal gene transfer (HGT) is an important mechanism contributing to genetic innovation of fungi. However, it remains unclear whether HGT has played a role in creating the enormous chemical diversity of fungal terpenoids. Here we report that fungi have acquired terpene synthase genes (TPSs), which encode pivotal enzymes for terpenoid biosynthesis, from bacteria through HGT. Phylogenetic analysis placed the majority of fungal and bacterial TPS genes from diverse taxa into two clades, indicating ancient …

Delineating The Role Of Fanca In Glucose-Stimulated Insulin Secretion In Β Cells Through Its Protein Interactome, Dragana Lagundzin, Wen-Feng Hu, Henry C. H. Law, Kimiko L. Krieger, Fangfang Qiao, Emalie J. Clement, Andjela T. Drincic, Olgica Nedic, Michael J. Naldrett, Sophie Alvarez, Nicholas T. Woods

Nebraska Center for Biotechnology: Faculty and Staff Publications

Hyperinsulinemia affects 72% of Fanconi anemia (FA) patients and an additional 25% experience lowered glucose tolerance or frank diabetes. The underlying molecular mechanisms contributing to the dysfunction of FA pancreas β cells is unknown. Therefore, we sought to evaluate the functional role of FANCA, the most commonly mutated gene in FA, in glucosestimulated insulin secretion (GSIS). This study reveals that FANCA or FANCB knockdown impairs GSIS in human pancreas β cell line EndoC-βH3. To identify potential pathways by which FANCA might regulate GSIS, we employed a proteomics approach to identify FANCA protein interactions in EndoC-βH3 differentially regulated in response to …

The Impact Of Extreme Virtual Elevation Above Grade On Construction Workers' Physiological Responses, Physical Responses, And Task Performance, Mahmoud Habibnezhad

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

On average, in every two work hours, one person dies from work-related injuries at construction sites. Most incidents are due to falling from elevated surfaces. Slips, trips, and loss of balance are the main causes. Studies suggest that instigating visual mismatch and physiological changes are among the most important reasons behind falling from narrow elevated surfaces. By using advanced virtual reality models, this dissertation aims to highlight some of the possible effects of a destabilizing environment (i.e., elevation above grade) on workers’ physiological responses and task performance. More specifically, this dissertation strives to find potential effects of elevation above grade …

Comparative Kinetic Modeling Of Growth And Molecular Hydrogen Overproduction By Engineered Strains Of Thermotoga Maritima, Raghuveer Singh, Rahul Tevatia, Derrick White, Yaşar Demirel, Paul H. Blum

Department of Chemical and Biomolecular Engineering: Faculty Publications

Thermotoga maritima is an anaerobic hyperthermophilic bacterium known for its high amounts of hydrogen (H₂) production. In the current study, the kinetic modeling was applied on the engineered strains of T. maritima that surpassed the natural H₂ production limit. The study generated a kinetic model explaining H₂ overproduction and predicted a continuous fermentation system. A Leudking-Piret equation-based model predicted that H₂ production by Tma200 (0.217 mol-H₂ g^–1-biomass) and Tma100 (0.147 mol-H₂ g^–1-biomass) were higher than wild type (0.096 mol-H₂ g^–1 -biomass) with reduced rates of maltose utilization. …

Manipulation Of The Precursor Supply For High-Level Production Of Longifolene By Metabolically Engineered Escherichia Coli, Yujin Cao, Rubing Zhang, Wei Liu, Guang Zhao, Wei Niu, Jiantao Guo, Mo Xian, Huizhou Liu

Department of Chemical and Biomolecular Engineering: Faculty Publications

Longifolene is a naturally occurring tricyclic sesquiterpene widely used in many different fields. Up to now, this valuable terpene was mainly manufactured from the high-boiling fraction of certain pine resins. Microbial production can be a promising alternative to the extraction from natural plant sources. Here, we present the metabolic engineering strategy to assemble biosynthetic pathway for longifolene production in Escherichia coli. E. coli was rendered to produce longifolene by heterologously expressing a codon optimized longifolene synthase from Picea abies. Augmentation of the metabolic flux to farnesyl pyrophosphate (FPP) by different FPP synthases conferred a 1.8-fold increase in longifolene …

Uncoupling Fermentative Synthesis Of Molecular Hydrogen From Biomass Formation In Thermotoga Maritima, Raghuveer Singh, Derrick White, Yaşar Demirel, Robert Kelley, Kenneth Noll, Paul H. Blum

Department of Chemical and Biomolecular Engineering: Faculty Publications

When carbohydrates are fermented by the hyperthermophilic anaerobe Thermotoga maritima, molecular hydrogen (H₂) is formed in strict proportion to substrate availability. Excretion of the organic acids acetate and lactate provide an additional sink for removal of excess reductant. However, mechanisms controlling energy management of these metabolic pathways are largely unexplored. To investigate this topic, transient gene inactivation was used to block lactate production as a strategy to produce spontaneous mutant cell lines that overproduced H₂ through mutation of unpredicted genetic targets. Single-crossover homologous chromosomal recombination was used to disrupt lactate dehydrogenase (encoded by ldh) with …

Using Synthetic Lethality To Sensitize Pediatric Brain Cancer Cells To The Dna Damaging Effects Of Radiation Therapy, Megan Ruckman, Rose Nelson, Forrest Kievit

UCARE: Research Products

Brain tumors are the leading cause of cancer related deaths in children. As a treatment, radiotherapy is very effective, but it also comes with many severe side effects, such as radiation-induced adverse developmental and psychosocial effects.² Cancer, because it is a mutagenic disease, is by definition a disease of DNA repair pathways. Here we utilize drugs to inhibit various DNA repair pathways with the purpose of sensitizing cancer cells to radiotherapy so that lower doses may be used. Hopefully this would improve the lifelong outcomes of patients that would otherwise not survive or would be left with lifelong neurocognitive …

Preparation And Characterization Of Functionalized Heparin-Loaded Poly-Ɛ-Caprolactone Fibrous Mats To Prevent Infection With Human Papillomaviruses, Daniela Gonzalez, Jorge Ragusa, Peter C. Angeletti, Gustavo F. Larsen

Department of Chemical and Biomolecular Engineering: Faculty Publications

In this study, heparin-loaded poly-ε-caprolactone (PCL) fibrous mats were prepared and characterized based on their physical, cytotoxic, thermal, and biological properties. The main objective of the work described here was to test the hypothesis that incorporation of heparin into a PCL carrier could serve as bio-compatible material capable of inhibiting Human Papillomavirus (HPV) infection. The idea of firmly anchoring heparin to capture soluble virus, vs. a slow heparin release to inhibit a virus in solution was tested. Thus, one material was produced via conventional heparin matrix encapsulation and electrohydrodynamic fiber processing in one step. A second type of material was …

Design Of A Distributed Real-Time E-Health Cyber Ecosystem With Collective Actions: Diagnosis, Dynamic Queueing, And Decision Making, Yanlin Zhou

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

In this thesis, we develop a framework for E-health Cyber Ecosystems, and look into different involved actors. The three interested parties in the ecosystem including patients, doctors, and healthcare providers are discussed in 3 different phases. In Phase 1, machine-learning based modeling and simulation analysis is performed to remotely predict a patient's risk level of having heart diseases in real time. In Phase 2, an online dynamic queueing model is devised to pair doctors with patients having high risk levels (diagnosed in Phase 1) to confirm the risk, and provide help. In Phase 3, a decision making paradigm is proposed …

Dynamic Classification Of Moisture Stress Using Canopy And Leaf Temperature Responses To A Step Changes Of Incident Radiation, Erin E. Stevens, George E. Meyer, Ellen T. Paparozzi

Honors Program: Senior Projects (Public)

Environmental conditions affect plant productivity and understanding how plants respond to drought stress can be measured in different ways. This study focused on measuring leaf response time to induced water stress. Leaf response time to a step increase and step decrease in radiation was computed for four species of well-watered and water-stressed plants in a controlled environment. The canopy temperature was measured with an infrared thermometer and a thermal imaging camera. Thermal images were analyzed to determine the average temperature of a selected single, unobstructed leaf at the top of the canopy. Both the canopy response time and the single …

Ring And Peg Simulation For Minimally Invasive Surgical Robot, Evan Brown

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Surgical procedures utilizing minimally invasive laparoscopic techniques have shown less complications, better cosmetic results, and less time in the hospital than conventional surgery. These advantages are partially offset by inherent difficulties of the procedures which include an inverted control scheme, instrument clashing, and loss of triangulation. Surgical robots have been designed to overcome the limitations, the Da Vinci being the most widely used. A dexterous in vivo, two-armed robot, designed to enter an insufflated abdomen with a limited insertion profile and expand to perform a variety of operations, has been created as a less expensive, versatile alternative to the Da …

A Strategic Audit Of Medtronic Plc, Jozzy Carter

Honors Program: Senior Projects (Public)

Humans will always have a need for healthcare, and as the world continues to innovate in the tech space, consumers will demand advances in medicine and medical devices. Medtronic is at the forefront of this innovation but faces intense competition in the medical technologies industry. This poses the question: what can Medtronic do to continue its growth and stay competitive in this space? This paper offers an analysis of Medtronic as a medical device company by offering insight to its competitive advantage, financials, business mix, and value chain. It also analyzes the forces that affect Medtronic using SWOT, PEST, and …

Eigenstrain As A Mechanical Set-Point Of Cells, Shengmao Lin, Marsha C. Lampi, Cynthia A. Reinhart-King, Gary C.P. Tsui, Jian Wang, Carl A. Nelson, Linxia Gu

Department of Mechanical and Materials Engineering: Faculty Publications

Cell contraction regulates how cells sense their mechanical environment. We sought to identify the set-point of cell contraction, also referred to as tensional homeostasis. In this work, bovine aortic endothelial cells (BAECs), cultured on substrates with different stiffness, were characterized using traction force microscopy (TFM). Numerical models were developed to provide insights into the mechanics of cell–substrate interactions. Cell contraction was modeled as eigenstrain which could induce isometric cell contraction without external forces. The predicted traction stresses matched well with TFM measurements. Furthermore, our numerical model provided cell stress and displacement maps for inspecting the fundamental regulating mechanism of cell …

Efficient One‑Step Fusion Pcr Based On Dual‑Asymmetric Primers And Two‑Step Annealing, Yilan Liu, Jinjin Chen, Anders Thygesen

Department of Chemical and Biomolecular Engineering: Faculty Publications

Gene splicing by fusion PCR is a versatile and widely used methodology, especially in synthetic biology. We here describe a rapid method for splicing two fragments by one-round fusion PCR with a dual-asymmetric primers and two-step annealing (ODT) method. During the process, the asymmetric intermediate fragments were generated in the early stage. Thereafter, they were hybridized in the subsequent cycles to serve as template for the target full-length product. The process parameters such as primer ratio, elongation temperature and cycle numbers were optimized. In addition, the fusion products produced with this method were successfully applied in seamless genome editing. The …

Multiple Factors Drive Variation Of Forest Root Biomass In Southwestern China, Hao Zhang, Kelin Wang, Zhaoxia Zeng, Zhigang Zou, Yanfang Xu, Fuping Zeng

Nebraska Center for Biotechnology: Faculty and Staff Publications

The roots linking the above-ground organs and soil are key components for estimating net primary productivity and carbon sequestration of forests. The patterns and drivers of root biomass in forest have not been examined well at the regional scale, especially for the widely distributed forest ecosystems in southwestern China. We attempted to determine the spatial patterns of root biomass (RB, Mg/ha), annual increment root biomass (AIRB, Mg/ha/year), ratio of root and above-ground (RRA), and the relative contributions of abiotic and biotic factors that drive the variation of root biomass. Forest biomass and multiple factors (climate, soil, forest types, and stand …

Diversity And Functional Evolution Of Terpene Synthases In Dictyostelid Social Amoebae, Xinlu Chen, Tobias G. Kollner, Gad Shaulsky, Qidong Jia, Jeroen S. Dickschat, Jonathan Gershenzon, Feng Chen

Nebraska Center for Biotechnology: Faculty and Staff Publications

Dictyostelids, or social amoebae, have a unique life style in forming multicellular fruiting bodies from unicellular amoeboids upon starvation. Recently, dictyostelids were found to contain terpene synthase (TPS) genes, a gene type of secondary metabolism previously known to occur only in plants, fungi and bacteria. Here we report an evolutionary functional study of dictyostelid TPS genes. The number of TPS genes in six species of dictyostelids examined ranges from 1 to 19; and the model species Dictyostelium purpureum contains 12 genes. Using in vitro enzyme assays, the 12 TPS genes from D. purpureum were shown to encode functional enzymes with …