Other Biochemistry, Biophysics, and Structural Biology Commons^™

Polyglycine Acts As A Rejection Signal For Protein Transport At The Chloroplast Envelope, Joshua K. Endow, Agostinho Gomes Rocha, Amy J. Baldwin, Rebecca L. Roston, Toshio Yamaguchi, Hironari Kamikubo, Kentaro Inoue

Department of Biochemistry: Faculty Publications

PolyGly is present in many proteins in various organisms. One example is found in a transmembrane β-barrel protein, translocon at the outer-envelope-membrane of chloroplasts 75 (Toc75). Toc75 requires its N-terminal extension (t75) for proper localization. t75 comprises signals for chloroplast import (n75) and envelope sorting (c75) in tandem. n75 and c75 are removed by stromal processing peptidase and plastidic type I signal peptidase 1, respectively. PolyGly is present within c75 and its deletion or substitution causes mistargeting of Toc75 to the stroma. Here we have examined the properties of polyGly-dependent protein targeting using two soluble passenger proteins, the mature portion …

Mutation In Atg5 Reduces Autophagy And Leads To Ataxia With Developmental Delay, Myungjin Kim, Erin Sandford, Damian Gatica, Yu Qiu, Xu Liu, Yumei Zheng, Brenda A. Schulman, Jishu Xu, Ian Semple, Seung-Hyun Ro, Boyoung Kim, R. Nehir Mavioglu, Aslihan Tolun, Andras Jipa, Szabolcs Takats, Manuela Karpati, Jun Z. Li, Zuhal Yapici, Gabor Juhasz, Jun Hee Lee, Daniel J. Klionsky, Margit Burmeister

Department of Biochemistry: Faculty Publications

Autophagy is required for the homeostasis of cellular material and is proposed to be involved in many aspects of health. Defects in the autophagy pathway have been observed in neurodegenerative disorders; however, no genetically-inherited pathogenic mutations in any of the core autophagy-related (ATG) genes have been reported in human patients to date. We identified a homozygous missense mutation, changing a conserved amino acid, in ATG5 in two siblings with congenital ataxia, mental retardation, and developmental delay. The subjects’ cells display a decrease in autophagy flux and defects in conjugation of ATG12 to ATG5. The homologous mutation in yeast …

Novel Acyltranserases And Methods Of Using, Edgar B. Cahoon, Umidjon Iskandarov, Hae Jin Kim, Jillian Collins-Silva

Department of Biochemistry: Faculty Publications

Provided herein are novel acyltransferases and methods of using Such novel acyltransferases in making medium-chain fatty acids.

Can Chilling Tolerance Of C4 Photosynthesis In Miscanthus Be Transferred To Sugarcane?, Katarzyna Glowacka, Aasifuddin Ahmed, Shailendra Sharma, Tom Abbott, Jack C. Comstock, Stephen P. Long, Erik J. Sacks

Department of Biochemistry: Faculty Publications

The goal of this study was to investigate whether chilling tolerance of C₄ photosynthesis in Miscanthus can be transferred to sugarcane by hybridization. Net leaf CO₂ uptake (A_sat) and the maximum operating efficiency of photosystem II (Ф_PSII) were measured in warm conditions (25 °C/20 °C), and then during and following a chilling treatment of 10 °C/5 °C for 11 day in controlled environment chambers. Two of three hybrids (miscanes), ‘US 84-1058’ and ‘US 87-1019’, did not differ significantly from the chilling tolerant M. xgiganteus ‘Illinois’ (Mxg), for A_sat, and Φ …

High-Throughput Mutation, Selection, And Phenotype Screening Of Mutant Methanogenic Archaea, Mary E. Walter, Alicia Ortiz, Casey Sondgeroth, Nathan M. Sindt, Nikolas Duszenko, Jennie L. Catlett, You Zhou, Shah R. Valloppilly, Christopher Anderson, Samodha Fernando, Nicole R. Buan

Department of Biochemistry: Faculty Publications

Bacterial and archaeal genomes can contain 30% or more hypothetical genes with no predicted function. Phylogenetically deep-branching microbes, such as methane-producing archaea (methanogens), contain up to 50% genes with unknown function. In order to formulate hypotheses about the function of hypothetical gene functions in the strict anaerobe, Methanosarcina acetivorans, we have developed high-throughput anaerobic techniques to UV mutagenize, screen, and select for mutant strains in 96-well plates. Using these approaches we have isolated 10 mutant strains that exhibit a variety of physiological changes including increased or decreased growth rate relative to the parent strain when cells use methanol and/or …

Pluralistic And Stochastic Gene Regulation: Examples, Models And Consistent Theory, Elisa N. Salas, Jiang Shu, Matyas F. Cserhati, Donald P. Weeks, Istvan Ladunga

Department of Biochemistry: Faculty Publications

We present a theory of pluralistic and stochastic gene regulation. To bridge the gap between empirical studies and mathematical models, we integrate pre-existing observations with our meta-analyses of the ENCODE ChIP-Seq experiments. Earlier evidence includes fluctuations in levels, location, activity, and binding of transcription factors, variable DNA motifs, and bursts in gene expression. Stochastic regulation is also indicated by frequently subdued effects of knockout mutants of regulators, their evolutionary losses/gains and massive rewiring of regulatory sites. We report wide-spread pluralistic regulation in ≈800 000 tightly co-expressed pairs of diverse human genes. Typically, half of ≈50 observed regulators bind to both …

Mutual Information Upper Bound Of Molecular Communication Based On Cell Metabolism, Massimiliano Pierobon, Zahmeeth Sakkaff, Jennie L. Catlett, Nicole R. Buan

Department of Biochemistry: Faculty Publications

Synthetic biology is providing novel tools to engineer cells and access the basis of their molecular information processing, including their communication channels based on chemical reactions and molecule exchange. Molecular communication is a discipline in communication engineering that studies these types of communications and ways to exploit them for novel purposes, such as the development of ubiquitous and heterogeneous communication networks to interconnect biological cells with nano and biotechnology-enabled devices, i.e., the Internet of Bio-Nano Things. One major problem in synthetic biology stands in the development of reliable techniques to control the engineered cells from the external environment. In this …

Mechanistic Nanotherapeutic Approach Based On Sirna-Mediated Dj-1 Protein Suppression For Platinum-Resistant Ovarian Cancer, Canan Schumann, Stephanie Chan, Oleh Khalimonchuk, Shannon Khal, Vitaliya Moskal, Vidhi Shah, Adam W. G. Alani, Olena Taratula, Oleh Taratula

Department of Biochemistry: Faculty Publications

We report an efficient therapeutic modality for platinum resistant ovarian cancer based on siRNAmediated suppression of a multifunctional DJ-1 protein that is responsible for the proliferation, growth, invasion, oxidative stress and overall survival of various cancers. The developed therapeutic strategy can work alone or in concert with a low dose of the first line chemotherapeutic agent cisplatin, to elicit a maximal therapeutic response. To achieve an efficient DJ-1 knockdown, we constructed the polypropylenimine dendrimer-based nanoplatform targeted to LHRH receptors overexpressed on ovarian cancer cells. The quantitative PCR and western immunoblotting analysis, revealed that the delivered DJ-1 siRNA downregulated the expression …

Engineering A Trifunctional Proline Utilization A Chimaera By Fusing A Dna-Binding Domain To A Bifunctional Puta, Benjamin W. Arentson, Erin L. Hayes, Weidong Zhu, John J. Tanner, Donald F. Becker

Department of Biochemistry: Faculty Publications

Proline utilization A (PutA) is a bifunctional flavoenzyme with proline dehydrogenase (PRODH) and Δ¹-pyrroline-5- carboxylate (P5C) dehydrogenase (P5CDH) domains that catalyses the two-step oxidation of proline to glutamate. Trifunctional PutAs also have an N-terminal ribbon–helix–helix (RHH) DNA-binding domain and moonlight as autogenous transcriptional repressors of the put regulon. A unique property of trifunctional PutA is the ability to switch functions from DNA-bound repressor to membrane-associated enzyme in response to cellular nutritional needs and proline availability. In the present study, we attempt to construct a trifunctional PutA by fusing the RHH domain of Escherichia coli PutA (EcRHH) to the …

Antisense Oligonucleotides: Treatment Strategies And Cellular Internalization, Colton M. Miller, Ed Harris

Department of Biochemistry: Faculty Publications

The clinical application of antisense oligonucleotides (ASOs) is becoming more of a reality as several drugs have been approved for the treatment of human disorders and many others are in various phases in development and clinical trials. ASOs are short DNA/RNA oligos which are heavily modified to increase their stability in biological fluids and retain the properties of creating RNA-RNA and DNA-RNA duplexes that knock-down or correct genetic expression. This review outlines several strategies that ASOs utilize for the treatment of various congenital diseases and syndromes that develop with aging. In addition, we discuss some of the mechanisms for specific …

Role Of Apoptotic Hepatocytes In Hcv Dissemination: Regulation By Acetaldehyde, Murali Ganesan, Sathish Kumar Natarajan, Jinjin Zhang, Justin L. Mott, Larisa I. Poluektova, Benita L. Mcvicker, Kusum K. Kharbanda, Dean J. Tuma, Natalie A. Osna

Department of Biochemistry: Faculty Publications

Alcohol consumption exacerbates hepatitis C virus (HCV) pathogenesis and promotes disease progression, although the mechanisms are not quite clear. We have previously observed that acetaldehyde (Ach) continuously produced by the acetaldehyde-generating system (AGS), temporarily enhanced HCV RNA levels, followed by a decrease to normal or lower levels, which corresponded to apoptosis induction. Here, we studied whether Ach-induced apoptosis caused depletion of HCV-infected cells and what role apoptotic bodies (AB) play in HCV-alcohol crosstalk. In liver cells exposed to AGS, we observed the induction of miR-122 and miR-34a. As miR-34a has been associated with apoptotic signaling and miR-122 with HCV replication, …

Inhibition Of Protein Ubiquitination By Paraquat And 1-Methyl-4-Phenylpyridinium Impairs Ubiquitin-Dependent Protein Degradation Pathways, Juliana Navarro-Yepes, Anandhan Annadurai, Erin Bradley, Iryna Bohovych, Bo Yarabe, Annemieke De Jong, Huib Ovaa, You Zhou, Oleh Khalimonchuk, Betzabet Quintanilla-Vega, Rodrigo Franco

Department of Biochemistry: Faculty Publications

Intracytoplasmic inclusions of protein aggregates in dopaminergic cells (Lewy bodies) are the pathological hallmark of Parkinson’s disease (PD). Ubiquitin (Ub), alpha [α]-synuclein, p62/sequestosome 1 and oxidized proteins are major components of Lewy bodies. However, the mechanisms involved in the impairment of misfolded/oxidized protein degradation pathways in PD are still unclear. PD is linked to mitochondrial dysfunction and environmental pesticide exposure. In this work, we evaluated the effect of the pesticide paraquat (PQ) and the mitochondrial toxin 1-methyl-4-phenylpyridinium (MPP⁺) on Ub-dependent protein degradation pathways. No increase in the accumulation of Ub-bound proteins or aggregates was observed in dopaminergic cells …

Potassium And The K+/H+ Exchanger Kha1p Promote Binding Of Copper To Apofet3p Multi-Copper Ferroxidase, Xiaobin Wu, Heejeong Kim, Javier Seravalli, Joseph J. Barycki, P. John Hart, David W. Gohara, Enrico Di Cera, Won Hee Jung, Daniel J. Kosman, Jaekwon Lee

Department of Biochemistry: Faculty Publications

Acquisition and distribution of metal ions support a number of biological processes. Here we show that respiratory growth of and iron acquisition by the yeast Saccharomyces cerevisiae relies on potassium (K⁺) compartmentalization to the trans-Golgi network via Kha1p, a K⁺/H⁺ exchanger. K⁺ in the trans-Golgi network facilitates binding of copper to the Fet3p multi-copper ferroxidase. The effect of K⁺ is not dependent on stable binding with Fet3p or alteration of the characteristics of the secretory pathway. The data suggest that K⁺ acts as a chemical factor in Fet3p maturation, a …

Analysis Of Oligomerization Properties Of Heme A Synthase Provides Insights Into Its Function In Eukaryotes, Samantha Swenson, Andrew Cannon, Nicholas J. Harris, Nicholas G. Taylor, Jennifer L. Fox, Oleh Khalimonchuk

Department of Biochemistry: Faculty Publications

Heme a is an essential cofactor for function of cytochrome c oxidase in the mitochondrial electron transport chain. Several evolutionarily conserved enzymes have been implicated in the biosynthesis of heme a, including the heme a synthase Cox15. However, the structure of Cox15 is unknown, its enzymatic mechanism and the role of active site residues remain debated, and recent discoveries suggest additional chaperone-like roles for this enzyme. Here, we investigated Cox15 in the model eukaryote Saccharomyces cerevisiae via several approaches to examine its oligomeric states and determine the effects of active site and human pathogenic mutations. Our results indicate that Cox15 …

Alcoholic Vs Non-Alcoholic Fatty Liver In Rats: Distinct Differences In Endocytosis And Vesicle Trafficking Despite Similar Pathology, Karuna Rasineni, Daniel D. Penrice, Sathish Kumar Natarajan, Mark A. Mcniven, Benita L. Mcvicker, Kusum K. Kharbanda, Carol A. Casey, Edward N. Harris

Department of Biochemistry: Faculty Publications

Background: Non-alcoholic and alcoholic fatty liver disease (NAFLD and AFLD, respectively) are major health problems, as patients with either condition can progress to hepatitis, fibrosis, and cirrhosis. Although histologically similar, key differences likely exist in these two models. For example, altered content of several vesicle trafficking proteins have been identified in AFLD, but their content in NAFLD is unknown. In this study, we compared select parameters in NAFLD and AFLD in a rat model.

Methods: We fed either Lieber- DeCarli liquid control or alcohol-containing (35 % as calories) diet (AFLD model) or lean or high-fat (12 or 60 % derived …

Atomic Resolution Experimental Phase Information Reveals Extensive Disorder And Bound 2-Methyl-2,4-Pentanediol In Ca2+-Calmodulin, Jiusheng Lin, Henry Van Den Bedem, Axel T. Brunger, Mark A. Wilson

Department of Biochemistry: Faculty Publications

Calmodulin (CaM) is the primary calcium signaling protein in eukaryotes and has been extensively studied using various biophysical techniques. Prior crystal structures have noted the presence of ambiguous electron density in both hydrophobic binding pockets of Ca²⁺-CaM, but no assignment of these features has been made. In addition, Ca²⁺-CaM samples many conformational substates in the crystal and accurately modeling the full range of this functionally important disorder is challenging. In order to characterize these features in a minimally biased manner, a 1.0 A resolution single-wavelength anomalous diffraction data set was measured for selenomethionine-substituted Ca²⁺-CaM. …

An Evaluation Of New And Established Methods To Determine T-Dna Copy Number And Homozygosity In Transgenic Plants, Katarzyna Glowacka, Johannes Kromdijk, Lauriebeth Leonelli, Krishna K. Niyogi, Tom E. Clemente, Stephen P. Long

Department of Biochemistry: Faculty Publications

Stable transformation of plants is a powerful tool for hypothesis testing.Arapid and reliable evaluation method of the transgenic allele for copy number and homozygosity is vital in analysing these transformations.Here the suitability of Southern blot analysis, thermal asymmetric interlaced (TAIL-)PCR, quantitative (q)PCR and digital droplet (dd)PCR to estimate T-DNA copy number, locus complexity and homozygosity were compared in transgenic tobacco. Southern blot analysis and ddPCR on three generations of transgenic offspring with contrasting zygosity and copy number were entirely consistent, whereas TAIL-PCR often underestimated copy number. qPCR deviated considerably from the Southern blot results and had lower precision and higher …

Confirmation Of Emx2 Protein Binding Partners, Cody Gillman

All Master's Theses

The neocortex is a structure within mammalian brains that processes sensory input from eyes, ears, and touch receptors and mediates the conscious use of skeletal muscles. The processing of information related to each of these types of functions is localized within discrete areas of the neocortex, which are separated by sharp borders. Proper development of these functional areas is regulated during embryogenesis by several transcription factors that are expressed in distinct gradients across the progenitor layer of the neocortex, the ventricular zone. Despite the vast amount of progress that has been made in describing how these transcription factors impact the …

Fatty Acid Transport Proteins: Targeting Fatp2 As A Gatekeeper Involved In The Transport Of Exogenous Fatty Acids, Paul N. Black, Constance Ahowesso, David Montefusco, Nipun Saini, Concetta C. Dirusso

Department of Biochemistry: Faculty Publications

The fatty acid transport proteins (FATP) are classified as members of the solute carrier 27 (Slc27) family of proteins based on their ability to function in the transport of exogenous fatty acids. These proteins, when localized to the plasma membrane or at intracellular membrane junctions with the endoplasmic reticulum, function as a gate in the regulated transport of fatty acids and thus represent a therapeutic target to delimit the acquisition of fatty acids that contribute to disease as in the case of fatty acid overload. To date, FATP1, FATP2, and FATP4 have been used as targets in the selection of …

Endoplasmic Reticulum-Associated Degradation Of Pca1p, A Polytopic Protein, Via Interaction With The Proteasome At The Membrane, Nathan Smith, David J. Adle, Miaoyun Zhao, Xiaojuan Quin, Heejeong Kim, Jaekwon Lee

Department of Biochemistry: Faculty Publications

Endoplasmic reticulum-associated degradation (ERAD) plays a critical role for destruction of terminally misfolded proteins at the secretory pathway. The system also regulates expression levels of several proteins such as Pca1p, a cadmium exporter in yeast. To gain better insight into the mechanisms underlying ERAD of Pca1p and other polytopic proteins by the proteasome in the cytosol, our study determined the roles for the molecular factors of ERAD in dislodging Pca1p from the ER. Inactivation of the 20S proteasome leads to accumulation of ubiquitinylated Pca1p in the ER membrane, suggesting a role for the proteasome in extraction of Pca1p from the …

Endoplasmic Reticulum-Associated Degradation Of Pca1p, A Polytopic Protein, Via Interaction With The Proteasome At The Membrane, Nathan Smith, David J. Adle, Miaoyun Zhao, Xiaojuan Qin, Heejeong Kim, Jaekwon Lee

Department of Biochemistry: Faculty Publications

Endoplasmic reticulum-associated degradation (ERAD) plays a critical role in the destruction of terminally misfolded proteins at the secretory pathway. The system also regulates expression levels of several proteins such as Pca1p, a cadmium exporter in yeast. To gain better insight into the mechanisms underlying ERAD of Pca1p and other polytopic proteins by the proteasome in the cytosol, our study determined the roles for the molecular factors of ERAD in dislodging Pca1p from the endoplasmic reticulum (ER). Inactivation of the 20S proteasome leads to accumulation of ubiquitinated Pca1p in the ER membrane, suggesting a role for the proteasome in extraction of …

Caloric Restriction Of Db/Db Mice Reverts Hepatic Steatosis And Body Weight With Divergent Hepatic Metabolism, Kyung Eun Kim, Youngae Jung, Soonki Min, Miso Nam, Rok Won Heo, Byeong Tak Jeon, Dae Hyun Song, Chin-Ok Yi, Eun Ae Jeong, Hwajin Kim, Jeonghyun Kim, Seon-Yong Jeong, Woori Kwak, Do Hyun Ryu, Tamas L. Horvath, Gu Seob Roh, Geum-Sook Hwang

Department of Biochemistry: Faculty Publications

Non-alcoholic fatty liver disease (NAFLD) is one of the most frequent causes of liver disease and its prevalence is a serious and growing clinical problem. Caloric restriction (CR) is commonly recommended for improvement of obesity-related diseases such as NAFLD. However, the effects of CR on hepatic metabolism remain unknown. We investigated the effects of CR on metabolic dysfunction in the liver of obese diabetic db/db mice. We found that CR of db/db mice reverted insulin resistance, hepatic steatosis, body weight and adiposity to those of db/m mice. H-NMR- and UPLC-QTOF-MS-based metabolite profiling data showed significant metabolic alterations related to lipogenesis, …

Synthesis And Transfer Of Galactolipids In The Chloroplast Envelope Membranes Of Arabidopsis Thaliana, Amélie Kelly, Barbara Kalisch, Georg Hölzl, Sandra Schulze, Juliane Thiele, Michael Melzer, Rebecca L. Roston, Christoph Benning, Peter Dörmann

Department of Biochemistry: Faculty Publications

Galactolipids [monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol

(DGDG)] are the hallmark lipids of photosynthetic

membranes. The galactolipid synthases MGD1 and DGD1

catalyze consecutive galactosyltransfer reactions but localize to the

inner and outer chloroplast envelopes, respectively, necessitating

intermembrane lipid transfer. Here we show that the N-terminal

sequence of DGD1 (NDGD1) is required for galactolipid transfer

between the envelopes. Different diglycosyllipid synthases (DGD1,

DGD2, and Chloroflexus glucosyltransferase) were introduced into

the dgd1-1 mutant of Arabidopsis in fusion with N-terminal extensions

(NDGD1 and NDGD2) targeting to the outer envelope. Reconstruction

of DGDG synthesis in the outer envelope membrane was

observed only with diglycosyllipid synthase fusion …

Evidence For Pipecolate Oxidase In Mediating Protection Against Hydrogen Peroxide Stress, Sathish Kumar Natarajan, Ezhumalai Muthukrishnan, Oleh Khalimonchuk, Justin L. Mott, Donald F. Becker

Department of Biochemistry: Faculty Publications

Pipecolate, an intermediate of the lysine catabolic pathway, is oxidized to Δ¹-piperideine-6-carboxylate (P6C) by the flavoenzyme lpipecolate oxidase (PIPOX). P6C spontaneously hydrolyzes to generate α-aminoadipate semialdehyde, which is then converted into α-aminoadipate acid by α-aminoadipatesemialdehyde dehydrogenase. l-pipecolate was previously reported to protect mammalian cells against oxidative stress. Here, we examined whether PIPOX is involved in the mechanism of pipecolate stress protection. Knockdown of PIPOX by small interference RNA abolished pipecolate protection against hydrogen peroxide-induced cell death in HEK293 cells suggesting a critical role for PIPOX. Subcellular fractionation analysis showed that PIPOX is localized in the mitochondria of HEK293 …

Ceramide Induces Human Hepcidin Gene Transcription Through Jak/Stat3 Pathway, Sizhao Lu, Sathish Kumar Natarajan, Justin L. Mott, Kusum K. Kharbanda, Duygu Dee Harrison-Findik

Department of Biochemistry: Faculty Publications

Changes in lipid metabolism and iron content are observed in the livers of patients with fatty liver disease. The expression of hepcidin, an iron-regulatory and acute phase protein synthesized by the liver, is also modulated. The potential interaction of lipid and iron metabolism is largely unknown.We investigated the role of lipid intermediate, ceramide in the regulation of human hepcidin gene, HAMP. Human hepatoma HepG2 cells were treated with cell-permeable ceramide analogs. Ceramide induced significant up-regulation of HAMP mRNA expression in HepG2 cells. The effect of ceramide on HAMP expression was mediated through transcriptional mechanisms because it was completely blocked …

Logical Modeling And Dynamical Analysis Of Cellular Networks, Wassim Abou-Jaoudé, Pauline Traynard, Pedro T. Monteiro, Julio Saez-Rodriguez, Tomáš Helikar, Denis Thieffry, Claudine Chaouiya

Department of Biochemistry: Faculty Publications

The logical (or logic) formalism is increasingly used to model regulatory and signaling networks. Complementing these applications, several groups contributed various methods and tools to support the definition and analysis of logical models. After an introduction to the logical modeling framework and to several of its variants, we review here a number of recent methodological advances to ease the analysis of large and intricate networks. In particular, we survey approaches to determine model attractors and their reachability properties, to assess the dynamical impact of variations of external signals, and to consistently reduce large models. To illustrate these developments, we further …

Case 62: Glycolysis, The Pentose Phosphate Pathway, And The Citric Acid Cycle In Tumorigenesis, Dr. Kathleen Cornely

Chemistry & Biochemistry Case Studies

Hypoxia-inducible factors are transcription factors that mediate the cellular response to hypoxia (low cellular oxygen concentration) by enhancing or suppressing the transcription of specific genes involved in metabolic pathways.

Chemical Inhibition Of Fatty Acid Absorption And Cellular Uptake Limits Lipotoxic Cell Death, Constance Ahowesso, Paul N. Black, Nipun Saini, David Montefusco, Jessica Chekal, Chrysa Malosh, Craig W. Lindsley, Shaun R. Stauffer, Concetta Dirusso

Department of Biochemistry: Faculty Publications

Chronic elevation of plasma free fatty acid (FFA) levels is commonly associated with obesity, type 2 diabetes, cardiovascular disease and some cancers. Experimental evidence indicates FFA and their metabolites contribute to disease development through lipotoxicity. Previously, we identified a specific fatty acid transport inhibitor CB16.2, a.k.a. Lipofermata, using high throughput screening methods. In this study, efficacy of transport inhibition was measured in four cell lines that are models for myocytes (mmC2C12), pancreatic ß-cells (rnINS-1E), intestinal epithelial cells (hsCaco-2), and hepatocytes (hsHepG2), as well as primary human adipocytes. The compound was effective in inhibiting uptake with IC₅₀s between 3 …

Fatty Acid Transport Protein-2 Inhibitor Grassofermata/Cb5 Protects Cells Against Lipid Accumulation And Toxicity, Nipun Saini, Paul N. Black, David Montefusco, Concetta Dirusso

Department of Biochemistry: Faculty Publications

The inhibition of the fatty acid uptake into non-adipose tissues provides an attractive target for prevention of lipotoxicity leading to obesity-associated non-alcoholic fatty liver disease and type 2 diabetes. Fatty acid transport proteins (FATPs) are bifunctional proteins involved in the uptake and activation of fatty acids by esterification with coenzyme A. Here we characterize Grassofermata/CB5, previously identified as a fatty acid uptake inhibitor directed against HsFATP2. The compound was effective in inhibiting the uptake of fatty acids in the low micro-molar range (IC₅₀ 8–11μM) and prevented palmitate-mediated lipid accumulation and cell death in cell lines that are models for …

Elongation Factor-P At The Crossroads Of The Host-Endosymbiont Interface, Andrei Rajkovic, Anne Witzky, William Navarre, Andrew J. Darwin, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Elongation factor P (EF-P) is an ancient bacterial translational factor that aids the ribosome in polymerizing oligo-prolines. EF-P structurally resembles tRNA and binds in-between the exit and peptidyl sites of the ribosome to accelerate the intrinsically slow reaction of peptidyl-prolyl bond formation. Recent studies have identified in separate organisms, two evolutionarily convergent EF-P post-translational modification systems (EPMS), split predominantly between gammaproteobacteria, and betaproteobacteria. In both cases EF-P receives a post-translational modification, critical for its function, on a highly conserved residue that protrudes into the peptidyl-transfer center of the ribosome. EPMSs are comprised of a gene(s) that synthesizes the precursor molecule …