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Miller SC, Tikhonova EB, Hernandez SM, Dufour JM, Karamyshev AL. Loss of Preproinsulin Interaction with Signal Recognition Particle Activates Protein Quality Control, Decreasing mRNA Stability. J Mol Biol 2024; 436:168492. [PMID: 38360088 DOI: 10.1016/j.jmb.2024.168492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Revised: 01/21/2024] [Accepted: 02/09/2024] [Indexed: 02/17/2024]
Abstract
Many insulin gene variants alter the protein sequence and result in monogenic diabetes due to insulin insufficiency. However, the molecular mechanisms of various disease-causing mutations are unknown. Insulin is synthesized as preproinsulin containing a signal peptide (SP). SPs of secreted proteins are recognized by the signal recognition particle (SRP) or by another factor in a SRP-independent pathway. If preproinsulin uses SRP-dependent or independent pathways is still debatable. We demonstrate by the use of site-specific photocrosslinking that the SRP subunit, SRP54, interacts with the preproinsulin SP. Moreover, SRP54 depletion leads to the decrease of insulin mRNA and protein expression, supporting the involvement of the RAPP protein quality control in insulin biogenesis. RAPP regulates the quality of secretory proteins through degradation of their mRNA. We tested five disease-causing mutations in the preproinsulin SP on recognition by SRP and on their effects on mRNA and protein levels. We demonstrate that the effects of mutations are associated with their position in the SP and their severity. The data support diverse molecular mechanisms involved in the pathogenesis of these mutations. We show for the first time the involvement of the RAPP protein quality control pathway in insulin biogenesis that is implicated in the development of neonatal diabetes caused by the Leu13Arg mutation.
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Affiliation(s)
- Sarah C Miller
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, 79430, USA
| | - Elena B Tikhonova
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, 79430, USA
| | - Sarah M Hernandez
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, 79430, USA
| | - Jannette M Dufour
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, 79430, USA
| | - Andrey L Karamyshev
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, 79430, USA.
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2
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Wang T, Tian S, Tikhonova EB, Karamyshev AL, Wang JJ, Zhang F, Wang D. The Enrichment of miRNA-Targeted mRNAs in Translationally Less Active over More Active Polysomes. Biology (Basel) 2023; 12:1536. [PMID: 38132362 PMCID: PMC10741098 DOI: 10.3390/biology12121536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 12/03/2023] [Accepted: 12/13/2023] [Indexed: 12/23/2023]
Abstract
miRNAs moderately inhibit the translation and enhance the degradation of their target mRNAs via cognate binding sites located predominantly in the 3'-untranslated regions (UTR). Paradoxically, miRNA targets are also polysome-associated. We studied the polysome association by the comparative translationally less-active light- and more-active heavy-polysome profiling of a wild type (WT) human cell line and its isogenic mutant (MT) with a disrupted DICER1 gene and, thus, mature miRNA production. As expected, the open reading frame (ORF) length is a major determinant of light- to heavy-polysome mRNA abundance ratios, but is rendered less powerful in WT than in MT cells by miRNA-regulatory activities. We also observed that miRNAs tend to target mRNAs with longer ORFs, and that adjusting the mRNA abundance ratio with the ORF length improves its correlation with the 3'-UTR miRNA-binding-site count. In WT cells, miRNA-targeted mRNAs exhibit higher abundance in light relative to heavy polysomes, i.e., light-polysome enrichment. In MT cells, the DICER1 disruption not only significantly abrogated the light-polysome enrichment, but also narrowed the mRNA abundance ratio value range. Additionally, the abrogation of the enrichment due to the DICER1 gene disruption, i.e., the decreases of the ORF-length-adjusted mRNA abundance ratio from WT to MT cells, exhibits a nearly perfect linear correlation with the 3'-UTR binding-site count. Transcription factors and protein kinases are the top two most enriched mRNA groups. Taken together, the results provide evidence for the light-polysome enrichment of miRNA-targeted mRNAs to reconcile polysome association and moderate translation inhibition, and that ORF length is an important, though currently under-appreciated, transcriptome regulation parameter.
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Affiliation(s)
- Tingzeng Wang
- Department of Environmental Toxicology, and The Institute of Environmental and Human Health (TIEHH), Texas Tech University, Lubbock, TX 79416, USA; (T.W.); (S.T.)
| | - Shuangmei Tian
- Department of Environmental Toxicology, and The Institute of Environmental and Human Health (TIEHH), Texas Tech University, Lubbock, TX 79416, USA; (T.W.); (S.T.)
| | - Elena B. Tikhonova
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; (E.B.T.); (A.L.K.)
| | - Andrey L. Karamyshev
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; (E.B.T.); (A.L.K.)
| | - Jing J. Wang
- Department of Cancer Biology and Genetics, James Comprehensive Cancer Center, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA;
| | - Fangyuan Zhang
- Department of Mathematics and Statistics, Texas Tech University, Lubbock, TX 79416, USA;
| | - Degeng Wang
- Department of Environmental Toxicology, and The Institute of Environmental and Human Health (TIEHH), Texas Tech University, Lubbock, TX 79416, USA; (T.W.); (S.T.)
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Gutierrez Guarnizo SA, Tikhonova EB, Karamyshev AL, Muskus CE, Karamysheva ZN. Translational reprogramming as a driver of antimony-drug resistance in Leishmania. Nat Commun 2023; 14:2605. [PMID: 37147291 PMCID: PMC10163012 DOI: 10.1038/s41467-023-38221-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 04/20/2023] [Indexed: 05/07/2023] Open
Abstract
Leishmania is a unicellular protozoan that has a limited transcriptional control and mostly uses post-transcriptional regulation of gene expression, although the molecular mechanisms of the process are still poorly understood. Treatments of leishmaniasis, pathologies associated with Leishmania infections, are limited due to drug resistance. Here, we report dramatic differences in mRNA translation in antimony drug-resistant and sensitive strains at the full translatome level. The major differences (2431 differentially translated transcripts) were demonstrated in the absence of the drug pressure supporting that complex preemptive adaptations are needed to efficiently compensate for the loss of biological fitness once they are exposed to the antimony. In contrast, drug-resistant parasites exposed to antimony activated a highly selective translation of only 156 transcripts. This selective mRNA translation is associated with surface protein rearrangement, optimized energy metabolism, amastins upregulation, and improved antioxidant response. We propose a novel model that establishes translational control as a major driver of antimony-resistant phenotypes in Leishmania.
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Affiliation(s)
- Sneider Alexander Gutierrez Guarnizo
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, 79430, USA
- Programa de Estudio y Control de Enfermedades Tropicales, Universidad de Antioquia. Medellín, Medellín, 050010, Colombia
| | - Elena B Tikhonova
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, 79430, USA
| | - Andrey L Karamyshev
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, 79430, USA.
| | - Carlos E Muskus
- Programa de Estudio y Control de Enfermedades Tropicales, Universidad de Antioquia. Medellín, Medellín, 050010, Colombia.
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Tikhonova EB, Gutierrez Guarnizo SA, Kellogg MK, Karamyshev A, Dozmorov IM, Karamysheva ZN, Karamyshev AL. Defective Human SRP Induces Protein Quality Control and Triggers Stress Response. J Mol Biol 2022; 434:167832. [PMID: 36210597 PMCID: PMC10024925 DOI: 10.1016/j.jmb.2022.167832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 08/27/2022] [Accepted: 09/13/2022] [Indexed: 12/15/2022]
Abstract
Regulation of Aberrant Protein Production (RAPP) is a protein quality control in mammalian cells. RAPP degrades mRNAs of nascent proteins not able to associate with their natural interacting partners during synthesis at the ribosome. However, little is known about the molecular mechanism of the pathway, its substrates, or its specificity. The Signal Recognition Particle (SRP) is the first interacting partner for secretory proteins. It recognizes signal sequences of the nascent polypeptides when they are exposed from the ribosomal exit tunnel. Here, we reveal the generality of the RAPP pathway on the whole transcriptome level through depletion of human SRP54, an SRP subunit. This depletion triggers RAPP and leads to decreased expression of the mRNAs encoding a number of secretory and membrane proteins. The loss of SRP54 also leads to the dramatic upregulation of a specific network of HSP70/40/90 chaperones (HSPA1A, DNAJB1, HSP90AA1, and others), increased ribosome associated ubiquitination, and change in expression of RPS27 and RPS27L suggesting ribosome rearrangement. These results demonstrate the complex nature of defects in protein trafficking, mRNA and protein quality control, and provide better understanding of their mechanisms at the ribosome.
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Affiliation(s)
- Elena B Tikhonova
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | | | - Morgana K Kellogg
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Alexander Karamyshev
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Igor M Dozmorov
- University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | | | - Andrey L Karamyshev
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA.
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Abstract
The signal recognition particle (SRP) is a ribonucleoprotein complex with dual functions. It co-translationally targets proteins with a signal sequence to the endoplasmic reticulum (ER) and protects their mRNA from degradation. If SRP is depleted or cannot recognize the signal sequence, then the Regulation of Aberrant Protein Production (RAPP) is activated, which results in the loss of secretory protein mRNA. If SRP recognizes the substrates but is unable to target them to ER, they may mislocalize or degrade. All these events lead to dramatic consequence for protein biogenesis, activating protein quality control pathways, and creating pressure on cell physiology, and might lead to the pathogenesis of disease. Indeed, SRP dysfunction is involved in many different human diseases, including: congenital neutropenia; idiopathic inflammatory myopathy; viral, protozoal, and prion infections; and cancer. In this work, we analyze diseases caused by SRP failure and discuss their possible molecular mechanisms.
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Affiliation(s)
- Morgana K Kellogg
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Elena B Tikhonova
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Andrey L Karamyshev
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, United States
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Hernandez SM, Tikhonova EB, Baca KR, Zhao F, Zhu X, Karamyshev AL. Unexpected Implication of SRP and AGO2 in Parkinson's Disease: Involvement in Alpha-Synuclein Biogenesis. Cells 2021; 10:2792. [PMID: 34685771 PMCID: PMC8534902 DOI: 10.3390/cells10102792] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 10/09/2021] [Accepted: 10/12/2021] [Indexed: 01/21/2023] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder classified by the loss of dopaminergic neurons in the substantia nigra pars compacta, the region of the brain that is responsible for motor control. Surviving neurons in this region contain aggregated protein alpha-Synuclein (αSyn) in the form of cytoplasmic inclusions, referred to as Lewy bodies. Changes in αSyn expression are also associated with PD and its progression. Previously, we demonstrated that signal recognition particle (SRP) and Argonaute 2 (AGO2) proteins are involved in protein quality control at the ribosome during translation. We also demonstrated that SRP has an mRNA protection function in addition to a protein targeting function, thus controlling mRNA and protein expression. In this study, we tested involvement of these factors in αSyn biogenesis. We hypothesize that loss of these factors may interfere with αSyn expression, and subsequently, be associated with PD. Using depletion assays in human cell culture and analysis of these proteins in the brains of deceased PD patients, we demonstrate that SRP and AGO2 are involved in the control of αSyn expression and AGO2 has reduced expression in PD. We show for the first time that SRP is involved in mRNA protection of αSyn, a protein that does not have a signal sequence or transmembrane span. Our findings suggest that SRP may interact with a hydrophobic domain in the middle of αSyn during translation. Understanding the molecular mechanisms controlling αSyn biogenesis in cells is vital to developing preventative therapies against PD.
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Affiliation(s)
- Sarah M. Hernandez
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; (S.M.H.); (E.B.T.); (K.R.B.)
| | - Elena B. Tikhonova
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; (S.M.H.); (E.B.T.); (K.R.B.)
| | - Kristen R. Baca
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; (S.M.H.); (E.B.T.); (K.R.B.)
- Center for the Integration of STEM Education and Research (CISER), Texas Tech University, Lubbock, TX 79409, USA
| | - Fanpeng Zhao
- Department of Pathology, Case Western Reserve University, Cleveland, OH 44106, USA; (F.Z.); (X.Z.)
| | - Xiongwei Zhu
- Department of Pathology, Case Western Reserve University, Cleveland, OH 44106, USA; (F.Z.); (X.Z.)
| | - Andrey L. Karamyshev
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; (S.M.H.); (E.B.T.); (K.R.B.)
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Markham KJ, Tikhonova EB, Scarpa AC, Hariharan P, Katsube S, Guan L. Complete cysteine-scanning mutagenesis of the Salmonella typhimurium melibiose permease. J Biol Chem 2021; 297:101090. [PMID: 34416232 PMCID: PMC8437787 DOI: 10.1016/j.jbc.2021.101090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 08/10/2021] [Accepted: 08/16/2021] [Indexed: 11/15/2022] Open
Abstract
The melibiose permease of Salmonella typhimurium (MelBSt) catalyzes the stoichiometric symport of galactopyranoside with a cation (H+, Li+, or Na+) and is a prototype for Na+-coupled major facilitator superfamily (MFS) transporters presenting from bacteria to mammals. X-ray crystal structures of MelBSt have revealed the molecular recognition mechanism for sugar binding; however, understanding of the cation site and symport mechanism is still vague. To further investigate the transport mechanism and conformational dynamics of MelBSt, we generated a complete single-Cys library containing 476 unique mutants by placing a Cys at each position on a functional Cys-less background. Surprisingly, 105 mutants (22%) exhibit poor transport activities (<15% of Cys-less transport), although the expression levels of most mutants were comparable to that of the control. The affected positions are distributed throughout the protein. Helices I and X and transmembrane residues Asp and Tyr are most affected by cysteine replacement, while helix IX, the cytoplasmic middle-loop, and C-terminal tail are least affected. Single-Cys replacements at the major sugar-binding positions (K18, D19, D124, W128, R149, and W342) or at positions important for cation binding (D55, N58, D59, and T121) abolished the Na+-coupled active transport, as expected. We mapped 50 loss-of-function mutants outside of these substrate-binding sites that suffered from defects in protein expression/stability or conformational dynamics. This complete Cys-scanning mutagenesis study indicates that MelBSt is highly susceptible to single-Cys mutations, and this library will be a useful tool for further structural and functional studies to gain insights into the cation-coupled symport mechanism for Na+-coupled MFS transporters.
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Affiliation(s)
- Kelsey J Markham
- Department of Cell Physiology & Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, School of Medicine, Lubbock, Texas, USA
| | - Elena B Tikhonova
- Department of Cell Physiology & Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, School of Medicine, Lubbock, Texas, USA
| | - Aaron C Scarpa
- Department of Cell Physiology & Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, School of Medicine, Lubbock, Texas, USA
| | - Parameswaran Hariharan
- Department of Cell Physiology & Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, School of Medicine, Lubbock, Texas, USA
| | - Satoshi Katsube
- Department of Cell Physiology & Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, School of Medicine, Lubbock, Texas, USA
| | - Lan Guan
- Department of Cell Physiology & Molecular Biophysics, Center for Membrane Protein Research, School of Medicine, Texas Tech University Health Sciences Center, School of Medicine, Lubbock, Texas, USA.
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Gutierrez Guarnizo SA, Tikhonova EB, Zabet-Moghaddam M, Zhang K, Muskus C, Karamyshev AL, Karamysheva ZN. Drug-Induced Lipid Remodeling in Leishmania Parasites. Microorganisms 2021; 9:microorganisms9040790. [PMID: 33918954 PMCID: PMC8068835 DOI: 10.3390/microorganisms9040790] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 03/29/2021] [Accepted: 04/07/2021] [Indexed: 12/20/2022] Open
Abstract
Leishmania parasites efficiently develop resistance against several types of drugs including antimonials, the primary antileishmanial drug historically implemented. The resistance to antimonials is considered to be a major risk factor for effective leishmaniasis treatment. To detect biomarkers/biopatterns for the differentiation of antimony-resistant Leishmania strains, we employed untargeted global mass spectrometry to identify intracellular lipids present in antimony sensitive and resistant parasites before and after antimony exposure. The lipidomic profiles effectively differentiated the sensitive and resistant phenotypes growing with and without antimony pressure. Resistant phenotypes were characterized by significant downregulation of phosphatidylcholines, sphingolipid decrease, and lysophosphatidylcholine increase, while sensitive phenotypes were characterized by the upregulation of triglycerides with long-chain fatty acids and a tendency toward the phosphatidylethanolamine decrease. Our findings suggest that the changes in lipid composition in antimony-resistant parasites contribute to the physiological response conducted to combat the oxidative stress unbalance caused by the drug. We have identified several lipids as potential biomarkers associated with the drug resistance.
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Affiliation(s)
- Sneider Alexander Gutierrez Guarnizo
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; (S.A.G.G.); (E.B.T.)
- Programa de Estudio y Control de Enfermedades Tropicales, Facultad de medicina, Universidad de Antioquia, Medellín 050010, Colombia;
| | - Elena B. Tikhonova
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; (S.A.G.G.); (E.B.T.)
| | | | - Kai Zhang
- Department of Biological Sciences, Texas Tech University, Lubbock, TX 79409, USA;
| | - Carlos Muskus
- Programa de Estudio y Control de Enfermedades Tropicales, Facultad de medicina, Universidad de Antioquia, Medellín 050010, Colombia;
| | - Andrey L. Karamyshev
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; (S.A.G.G.); (E.B.T.)
- Correspondence: (A.L.K.); (Z.N.K.); Tel.: +1-806-743-4102 (A.L.K.); +1-806-834-5075 (Z.N.K.)
| | - Zemfira N. Karamysheva
- Department of Biological Sciences, Texas Tech University, Lubbock, TX 79409, USA;
- Correspondence: (A.L.K.); (Z.N.K.); Tel.: +1-806-743-4102 (A.L.K.); +1-806-834-5075 (Z.N.K.)
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9
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Lee AK, Klein J, Fon Tacer K, Lord T, Oatley MJ, Oatley JM, Porter SN, Pruett-Miller SM, Tikhonova EB, Karamyshev AL, Wang YD, Yang P, Korff A, Kim HJ, Taylor JP, Potts PR. Translational Repression of G3BP in Cancer and Germ Cells Suppresses Stress Granules and Enhances Stress Tolerance. Mol Cell 2020; 79:645-659.e9. [PMID: 32692974 DOI: 10.1016/j.molcel.2020.06.037] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 05/10/2020] [Accepted: 06/29/2020] [Indexed: 02/08/2023]
Abstract
Stress granules (SGs) are membrane-less ribonucleoprotein condensates that form in response to various stress stimuli via phase separation. SGs act as a protective mechanism to cope with acute stress, but persistent SGs have cytotoxic effects that are associated with several age-related diseases. Here, we demonstrate that the testis-specific protein, MAGE-B2, increases cellular stress tolerance by suppressing SG formation through translational inhibition of the key SG nucleator G3BP. MAGE-B2 reduces G3BP protein levels below the critical concentration for phase separation and suppresses SG initiation. Knockout of the MAGE-B2 mouse ortholog or overexpression of G3BP1 confers hypersensitivity of the male germline to heat stress in vivo. Thus, MAGE-B2 provides cytoprotection to maintain mammalian spermatogenesis, a highly thermosensitive process that must be preserved throughout reproductive life. These results demonstrate a mechanism that allows for tissue-specific resistance against stress and could aid in the development of male fertility therapies.
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Affiliation(s)
- Anna K Lee
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Jonathon Klein
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Klementina Fon Tacer
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Tessa Lord
- Center for Reproductive Biology, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Melissa J Oatley
- Center for Reproductive Biology, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Jon M Oatley
- Center for Reproductive Biology, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Shaina N Porter
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Shondra M Pruett-Miller
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Elena B Tikhonova
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Andrey L Karamyshev
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Yong-Dong Wang
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Peiguo Yang
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Ane Korff
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Hong Joo Kim
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - J Paul Taylor
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA; Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Patrick Ryan Potts
- Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN, USA.
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10
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Karamyshev AL, Tikhonova EB, Karamysheva ZN. Translational Control of Secretory Proteins in Health and Disease. Int J Mol Sci 2020; 21:ijms21072538. [PMID: 32268488 PMCID: PMC7177344 DOI: 10.3390/ijms21072538] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 03/30/2020] [Accepted: 04/03/2020] [Indexed: 12/12/2022] Open
Abstract
Secretory proteins are synthesized in a form of precursors with additional sequences at their N-terminal ends called signal peptides. The signal peptides are recognized co-translationally by signal recognition particle (SRP). This interaction leads to targeting to the endoplasmic reticulum (ER) membrane and translocation of the nascent chains into the ER lumen. It was demonstrated recently that in addition to a targeting function, SRP has a novel role in protection of secretory protein mRNAs from degradation. It was also found that the quality of secretory proteins is controlled by the recently discovered Regulation of Aberrant Protein Production (RAPP) pathway. RAPP monitors interactions of polypeptide nascent chains during their synthesis on the ribosomes and specifically degrades their mRNAs if these interactions are abolished due to mutations in the nascent chains or defects in the targeting factor. It was demonstrated that pathological RAPP activation is one of the molecular mechanisms of human diseases associated with defects in the secretory proteins. In this review, we discuss recent progress in understanding of translational control of secretory protein biogenesis on the ribosome and pathological consequences of its dysregulation in human diseases.
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Affiliation(s)
- Andrey L. Karamyshev
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA;
- Correspondence: (A.L.K.); (Z.N.K.); Tel.: +1-806-743-4102 (A.L.K.); +1-806-834-5075 (Z.N.K.)
| | - Elena B. Tikhonova
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA;
| | - Zemfira N. Karamysheva
- Department of Biological Sciences, Texas Tech University, Lubbock, TX 79409, USA
- Correspondence: (A.L.K.); (Z.N.K.); Tel.: +1-806-743-4102 (A.L.K.); +1-806-834-5075 (Z.N.K.)
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11
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Hernandez SM, Tikhonova EB, Karamyshev AL. Protein-Protein Interactions in Alpha-Synuclein Biogenesis: New Potential Targets in Parkinson's Disease. Front Aging Neurosci 2020; 12:72. [PMID: 32256340 PMCID: PMC7092629 DOI: 10.3389/fnagi.2020.00072] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Accepted: 02/27/2020] [Indexed: 12/14/2022] Open
Abstract
Parkinson’s disease (PD) is a debilitating neurodegenerative disorder defined by a loss of dopamine-producing neurons in the substantia nigra in the brain. It is associated with cytosolic inclusions known as Lewy bodies. The major component of Lewy bodies is aggregated alpha-synuclein. The molecular mechanism of alpha-synuclein aggregation is not known. Our conceptual model is that alpha-synuclein aggregates due to a dysregulation of its interactions with other protein partners that are required for its biogenesis. In this mini review article, we identified alpha-synuclein interactions using both current literature and predictive pathway analysis. Alterations of these interactions may be crucial elements for the molecular mechanism of the protein aggregation and related pathology in the disease. Identification of alpha-synuclein interactions provides valuable tools to understand PD pathology and find new pharmacological targets for disease treatment.
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Affiliation(s)
- Sarah M Hernandez
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Elena B Tikhonova
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Andrey L Karamyshev
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, United States
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12
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Karamysheva ZN, Tikhonova EB, Karamyshev AL. Granulin in Frontotemporal Lobar Degeneration: Molecular Mechanisms of the Disease. Front Neurosci 2019; 13:395. [PMID: 31105517 PMCID: PMC6494926 DOI: 10.3389/fnins.2019.00395] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 04/08/2019] [Indexed: 01/01/2023] Open
Affiliation(s)
- Zemfira N Karamysheva
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, United States
| | - Elena B Tikhonova
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Andrey L Karamyshev
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, TX, United States
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13
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Karamysheva ZN, Tikhonova EB, Grozdanov PN, Huffman JC, Baca KR, Karamyshev A, Denison RB, MacDonald CC, Zhang K, Karamyshev AL. Polysome Profiling in Leishmania, Human Cells and Mouse Testis. J Vis Exp 2018. [PMID: 29683462 DOI: 10.3791/57600] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Proper protein expression at the right time and in the right amounts is the basis of normal cell function and survival in a fast-changing environment. For a long time, the gene expression studies were dominated by research on the transcriptional level. However, the steady-state levels of mRNAs do not correlate well with protein production, and the translatability of mRNAs varies greatly depending on the conditions. In some organisms, like the parasite Leishmania, the protein expression is regulated mostly at the translational level. Recent studies demonstrated that protein translation dysregulation is associated with cancer, metabolic, neurodegenerative and other human diseases. Polysome profiling is a powerful method to study protein translation regulation. It allows to measure the translational status of individual mRNAs or examine translation on a genome-wide scale. The basis of this technique is the separation of polysomes, ribosomes, their subunits and free mRNAs during centrifugation of a cytoplasmic lysate through a sucrose gradient. Here, we present a universal polysome profiling protocol used on three different models - parasite Leishmania major, cultured human cells and animal tissues. Leishmania cells freely grow in suspension and cultured human cells grow in adherent monolayer, while mouse testis represents an animal tissue sample. Thus, the technique is adapted to all of these sources. The protocol for the analysis of polysomal fractions includes detection of individual mRNA levels by RT-qPCR, proteins by Western blot and analysis of ribosomal RNAs by electrophoresis. The method can be further extended by examination of mRNAs association with the ribosome on a transcriptome level by deep RNA-seq and analysis of ribosome-associated proteins by mass spectroscopy of the fractions. The method can be easily adjusted to other biological models.
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Affiliation(s)
| | - Elena B Tikhonova
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center
| | - Petar N Grozdanov
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center
| | - James C Huffman
- Department of Biological Sciences, Texas Tech University; CISER (Center for the Integration of STEM Education & Research), Texas Tech University
| | - Kristen R Baca
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center; CISER (Center for the Integration of STEM Education & Research), Texas Tech University
| | - Alexander Karamyshev
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center
| | - R Brian Denison
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center
| | - Clinton C MacDonald
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center
| | - Kai Zhang
- Department of Biological Sciences, Texas Tech University
| | - Andrey L Karamyshev
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center;
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14
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Tikhonova EB, Parameswaran H, Su Y, Anowarul A, Guan L. Functional Inhibition of Sugar Transport by a Designed Novel Protein. Biophys J 2014. [DOI: 10.1016/j.bpj.2013.11.2080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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15
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Krishnamoorthy G, Tikhonova EB, Dhamdhere G, Zgurskaya HI. On the role of TolC in multidrug efflux: the function and assembly of AcrAB-TolC tolerate significant depletion of intracellular TolC protein. Mol Microbiol 2013; 87:982-97. [PMID: 23331412 DOI: 10.1111/mmi.12143] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/21/2012] [Indexed: 12/11/2022]
Abstract
TolC channel provides a route for the expelled drugs and toxins to cross the outer membrane of Escherichia coli. The puzzling feature of TolC structure is that the periplasmic entrance of the channel is closed by dense packing of 12 α-helices. Efflux pumps exemplified by AcrAB are proposed to drive the opening of TolC channel. How interactions with AcrAB promote the close-to-open transition in TolC remains unclear. In this study, we investigated in vivo the functional and physical interactions of AcrAB with the closed TolC and its conformer opened by mutations in the periplasmic entrance. We found that the two conformers of TolC are readily distinguishable in vivo by characteristic drug susceptibility, thiol modification and proteolytic profiles. However, these profiles of TolC variants respond neither to the in vivo stoichiometry of AcrAB:TolC nor to the presence of vancomycin, which is used often to assess the permeability of TolC channel. We further found that the activity and assembly of AcrAB-TolC tolerates significant changes in amounts of TolC and that only a small fraction of intracellular TolC is likely used to support efflux needs of E. coli. Our findings explain why TolC is not a good target for inhibition of multidrug efflux.
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Affiliation(s)
- Ganesh Krishnamoorthy
- Department of Chemistry and Biochemistry, University of Oklahoma, Stephenson Life Science Research Center, Norman, OK 73019, UK
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16
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Abstract
Surface plasmon resonance (SPR) is a powerful tool for kinetic analyses of protein-protein interactions. Here we describe the application of this method to study interactions of membrane proteins involved in multidrug efflux in Escherichia coli.These so-called multidrug efflux pumps comprise an inner membrane transporter, a periplasmic membrane fusion protein and an outer membrane channel. The three components are assembled into a protein conduit that enables bacteria to expel multiple drugs directly into the external medium bypassing the periplasm. The "across-two-membranes" transport mechanism makes tripartite transporters poorly amenable to biochemical analyses. Two out of three components are located in different membranes and must be studied in detergents or reconstituted into lipid bilayers to retain their functionality. Furthermore, cytoplasmic and exoplasmic domains of all three components perform different functions and must be oriented in a specific way to assemble functional complexes. The SPR approach provides means to overcome some of these problems in studies of protein assemblies that function in the context of two membranes.
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Affiliation(s)
- Elena B Tikhonova
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, USA
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17
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Abstract
Lipid-coated DNA nanoparticles (lipoplexes) are a powerful gene delivery tool with promising therapeutic applications. The mechanism of lipoplex assembly remains poorly understood. We explored DNA packing by a cationic lipid DSTAP (distearoyl trimethylammonium-propane) using magnetic tweezers. DSTAP-induced DNA condensation occurred as a series of bursts with the mean step size of 60-80 nm. The pause time preceding the steps could be approximated as a bimodal distribution, which reveals at least two distinct condensation pathways. The rapidly condensed DNA was more resilient to force-induced decondensation. The proportion of the stable, fast-formed complexes decreased at high salt concentrations. A similar trend was observed in bulk experiments. Lipoplexes assembled at low salt concentration more efficiently shielded DNA from fluorescent dyes and DNase even after transfer to the high salt conditions. These data reveal that lipoplex folding occurs via two parallel pathways even at the single molecule level. The progress through the two pathways can be monitored in real time using single DNA manipulations. The relative efficiency of the two pathways can be varied by external conditions.
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Affiliation(s)
- Zhiqiang Sun
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, USA
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18
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Zgurskaya HI, Yamada Y, Tikhonova EB, Ge Q, Krishnamoorthy G. Structural and functional diversity of bacterial membrane fusion proteins. Biochim Biophys Acta 2008; 1794:794-807. [PMID: 19041958 DOI: 10.1016/j.bbapap.2008.10.010] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2008] [Revised: 10/21/2008] [Accepted: 10/22/2008] [Indexed: 10/21/2022]
Abstract
Membrane Fusion Proteins (MFPs) are functional subunits of multi-component transporters that perform diverse physiological functions in both Gram-positive and Gram-negative bacteria. MFPs associate with transporters belonging to Resistance-Nodulation-cell Division (RND), ATP-Binding Cassette (ABC) and Major Facilitator (MF) superfamilies of proteins. Recent studies suggested that MFPs interact with substrates and play an active role in transport reactions. In addition, the MFP-dependent transporters from Gram-negative bacteria recruit the outer membrane channels to expel various substrates across the outer membrane into external medium. This review is focused on the diversity, structure and molecular mechanism of MFPs that function in multidrug efflux. Using phylogenetic approaches we analyzed diversity and representation of multidrug MFPs in sequenced bacterial genomes. In addition to previously characterized MFPs from Gram-negative bacteria, we identified MFPs that associate with RND-, MF- and ABC-type transporters in Gram-positive bacteria. Sequence analyses showed that MFPs vary significantly in size (200-650 amino acid residues) with some of them lacking the signature alpha-helical domain of multidrug MFPs. Furthermore, many transport operons contain two- or three genes encoding distinct MFPs. We further discuss the diversity of MFPs in the context of current views on the mechanism and structure of MFP-dependent transporters.
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Affiliation(s)
- Helen I Zgurskaya
- University of Oklahoma Department of Chemistry and Biochemistry 620 Parrington Oval, Room 208 Norman, OK 73019, USA.
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19
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Tikhonova EB, Devroy VK, Lau SY, Zgurskaya HI. Reconstitution of the Escherichia coli macrolide transporter: the periplasmic membrane fusion protein MacA stimulates the ATPase activity of MacB. Mol Microbiol 2007; 63:895-910. [PMID: 17214741 DOI: 10.1111/j.1365-2958.2006.05549.x] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Periplasmic membrane fusion proteins (MFPs) are essential components of the type I protein secretion systems and drug efflux pumps in Gram-negative bacteria. Previous studies suggested that MFPs connect the inner and outer membrane components of the transport systems and by this means co-ordinate the transfer of substrates across the two membranes. In this study, we purified and reconstituted the macrolide transporter MacAB from Escherichia coli. Here, MacA is a periplasmic MFP and MacB is an ABC-type transporter. Similar to other MFP-dependent transporters from E. coli, the in vivo function of MacAB requires the outer membrane channel TolC. The purified MacB displayed a basal ATPase activity in detergent micelles. This activity conformed to Michaelis-Menten kinetics but was unresponsive to substrates or accessory proteins. Upon reconstitution into proteoliposomes, the ATPase activity of MacB was strictly dependent on MacA. The catalytic efficiency of MacAB ATPase was more than 45-fold higher than the activity of MacB alone. Both the N- and C-terminal regions of MacA were essential for this activity. MacA stimulated MacB ATPase only in phospholipid bilayers and did not need the presence of macrolides. Our results suggest that MacA is a functional subunit of the MacB transporter.
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Affiliation(s)
- Elena B Tikhonova
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK 73019, USA
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20
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Abstract
Many transporters of Gram-negative bacteria involved in the extracellular secretion of proteins and the efflux of toxic molecules operate by forming intermembrane complexes. These complexes are proposed to span both inner and outer membranes and create a bridge across the periplasm. In this study, we analyzed interactions between the inner and outer membrane components of the tri-partite multidrug efflux pump AcrAB-TolC from Escherichia coli. We found that, once assembled, the intermembrane AcrAB-TolC complex is stable during the separation of the inner and outer membranes and subsequent purification. All three components of the complex co-purify when the affinity tag is attached to either of the proteins suggesting bi-partite interactions between AcrA, AcrB, and TolC. We show that antibiotics, the substrates of AcrAB-TolC, stabilize interactions within the complex. However, the formation of the AcrAB-TolC complex does not require an input of energy.
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Affiliation(s)
- Elena B Tikhonova
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, 73019, USA
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21
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Zgurskaya HI, Krishnamoorthy G, Tikhonova EB, Lau SY, Stratton KL. Mechanism of antibiotic efflux in Gram-negative bacteria. Front Biosci 2003; 8:s862-73. [PMID: 12957812 DOI: 10.2741/1134] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Active efflux of antibiotics mediated by multidrug transporters is a mechanistic basis of multidrug resistance in bacteria. The most versatile multidrug transporters are those found in Gram-negative bacteria. They have a high level of constitutive expression and provide an immediate response to structurally diverse antimicrobial agents including clinically important antibiotics. The versatility and efficiency of multidrug transporters in Gram-negative bacteria heavily depend on coupling of drug efflux with the transport across the outer membrane. The coupling is achieved through the assembly of multi-component protein complexes that span both the inner and the outer membranes of Gram-negative bacteria. In this review we discuss the mechanistic and structural features of multidrug efflux complexes with the major focus on the tight coupling of drug efflux with transport across the outer membrane.
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Affiliation(s)
- Helen I Zgurskaya
- University of Oklahoma, Department of Chemistry and Biochemistry, Norman, OK 73019, USA.
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22
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Abstract
Many multidrug transporters from gram-negative bacteria belong to the resistance-nodulation-cell division (RND) superfamily of transporters. RND-type multidrug transporters have an extremely broad substrate specificity and protect bacterial cells from the actions of antibiotics on both sides of the cytoplasmic membrane. They usually function as three-component assemblies spanning the outer and cytoplasmic membranes and the periplasmic space of gram-negative bacteria. The structural determinants of RND transporters responsible for multidrug recognition and complex assembly remain unknown. We constructed chimeric RND transporters composed of N-terminal residues of AcrB and C-terminal residues of MexB, the major RND-type transporters from Escherichia coli and Pseudomonas aeruginosa, respectively. The assembly of complexes and multidrug efflux activities of chimeric transporters were determined by coexpression of hybrid genes either with AcrA, the periplasmic component of the AcrAB transporter from E. coli, or with MexA and OprM, the accessory proteins of the MexAB-OprM pump from P. aeruginosa. We found that the specificity of interaction with the corresponding periplasmic component is encoded in the T60-V612 region of transporters. Our results also suggest that the large periplasmic loops of RND-type transporters are involved in multidrug recognition and efflux.
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Affiliation(s)
- Elena B Tikhonova
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019, USA
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23
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Ermakova IT, Starovoĭtov II, Tikhonova EB, Slepen'kin AV, Kashparov KI, Boronin AM. [Thiodiglycol metabolism in Alcaligenes xylosoxydans subsp. denitrificans]. Mikrobiologiia 2002; 71:604-10. [PMID: 12449625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
The investigation of the degradation of thiodiglycol (the major product of mustard gas hydrolysis) by Alcaligenes xylosoxydans subsp. denitrificans strain TD2 showed that thiodiglycol is metabolized through the oxidation of its primary alcohol groups and the subsequent cleavage of C-S bonds in the intermediate products, thiodiglycolic and thioglycolic acids. The end products of these reactions are SO4(2-) ions and acetate, the latter being involved in the central metabolism of strain TD2. The oxidation of the sulfur atom gives rise to diglycolsulfoxide, which is recalcitrant to further microbial degradation. Based on the data obtained, a metabolic pathway of thiodiglycol transformation by A. xylosoxydans subsp. denitrificans strain TD2 is proposed.
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Affiliation(s)
- I T Ermakova
- Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, pr. Nauki 5, Puschino, Moscow Oblast, 142290 Russia
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24
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Tikhonova EB, Ermakova IT, Slepen'kin AV, Kashparov KI, Starovoĭtov II, Boronin AM. [The bioutilization of thiodiglycol (a breakdown product of mustard gas): isolation of degraders and investigation of degradation conditions]. Mikrobiologiia 2002; 71:247-53. [PMID: 12024827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
The Alcaligenes xylosoxydans subsp. denitrificans strain TD1 capable of degrading thiodiglycol (TDG), a breakdown product of mustard gas, was isolated from soil contaminated with breakdown products of this chemical warfare agent. The selected stable variant of TD1 (strain TD2) can grow on TDG with a lag phase of 4-8 h and a specific growth rate of 0.04-0.045 h-1. Optimal conditions for the biodegradation of TDG (pH, the concentration of TDG in the medium, and its relative content with respect to the bacterial biomass) were determined. TDG was found to be degraded with the formation of diglycolsulfoxide and thiodiglycolic acid. The data obtained can be used to develop approaches to the bioremediation of mustard gas-contaminated soils.
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Affiliation(s)
- E B Tikhonova
- Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, pr. Nauki 5, Pushchino, Moscow Oblast, 142290 Russia
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