1
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Baumgartner JT, Habeeb Mohammad TS, Czub MP, Majorek KA, Arolli X, Variot C, Anonick M, Minor W, Ballicora MA, Becker DP, Kuhn ML. Gcn5-Related N-Acetyltransferases (GNATs) With a Catalytic Serine Residue Can Play Ping-Pong Too. Front Mol Biosci 2021; 8:646046. [PMID: 33912589 PMCID: PMC8072286 DOI: 10.3389/fmolb.2021.646046] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 02/22/2021] [Indexed: 02/06/2023] Open
Abstract
Enzymes in the Gcn5-related N-acetyltransferase (GNAT) superfamily are widespread and critically involved in multiple cellular processes ranging from antibiotic resistance to histone modification. While acetyl transfer is the most widely catalyzed reaction, recent studies have revealed that these enzymes are also capable of performing succinylation, condensation, decarboxylation, and methylcarbamoylation reactions. The canonical chemical mechanism attributed to GNATs is a general acid/base mechanism; however, mounting evidence has cast doubt on the applicability of this mechanism to all GNATs. This study shows that the Pseudomonas aeruginosa PA3944 enzyme uses a nucleophilic serine residue and a hybrid ping-pong mechanism for catalysis instead of a general acid/base mechanism. To simplify this enzyme's kinetic characterization, we synthesized a polymyxin B substrate analog and performed molecular docking experiments. We performed site-directed mutagenesis of key active site residues (S148 and E102) and determined the structure of the E102A mutant. We found that the serine residue is essential for catalysis toward the synthetic substrate analog and polymyxin B, but the glutamate residue is more likely important for substrate recognition or stabilization. Our results challenge the current paradigm of GNAT mechanisms and show that this common enzyme scaffold utilizes different active site residues to accomplish a diversity of catalytic reactions.
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Affiliation(s)
- Jackson T. Baumgartner
- Department of Chemistry and Biochemistry, San Francisco State University, San Francisco, CA, United States
| | | | - Mateusz P. Czub
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA, United States
- Center for Structural Genomics of Infectious Diseases (CSGID), University of Virginia, Charlottesville, VA, United States
| | - Karolina A. Majorek
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA, United States
- Center for Structural Genomics of Infectious Diseases (CSGID), University of Virginia, Charlottesville, VA, United States
| | - Xhulio Arolli
- Department of Chemistry and Biochemistry, Loyola University Chicago, Chicago, IL, United States
| | - Cillian Variot
- Department of Chemistry and Biochemistry, San Francisco State University, San Francisco, CA, United States
| | - Madison Anonick
- Department of Chemistry and Biochemistry, Loyola University Chicago, Chicago, IL, United States
| | - Wladek Minor
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, VA, United States
- Center for Structural Genomics of Infectious Diseases (CSGID), University of Virginia, Charlottesville, VA, United States
| | - Miguel A. Ballicora
- Department of Chemistry and Biochemistry, Loyola University Chicago, Chicago, IL, United States
| | - Daniel P. Becker
- Department of Chemistry and Biochemistry, Loyola University Chicago, Chicago, IL, United States
| | - Misty L. Kuhn
- Department of Chemistry and Biochemistry, San Francisco State University, San Francisco, CA, United States
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2
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Snell EH, Helliwell JR. Microgravity as an environment for macromolecular crystallization – an outlook in the era of space stations and commercial space flight. CRYSTALLOGR REV 2021. [DOI: 10.1080/0889311x.2021.1900833] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- E. H. Snell
- Hauptman-Woodward Medical Research Institute, Buffalo, NY, USA
- Materials Design and Innovation Department, SUNY Buffalo, Buffalo, NY, USA
| | - J. R. Helliwell
- Chemistry Department, University of Manchester, Manchester, UK
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3
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Phleomycin complex – Coordination mode and in vitro cleavage of DNA. J Inorg Biochem 2019; 195:71-82. [DOI: 10.1016/j.jinorgbio.2019.03.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 02/15/2019] [Accepted: 03/10/2019] [Indexed: 11/21/2022]
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4
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Aboalroub AA, Bachman AB, Zhang Z, Keramisanou D, Merkler DJ, Gelis I. Acetyl group coordinated progression through the catalytic cycle of an arylalkylamine N-acetyltransferase. PLoS One 2017; 12:e0177270. [PMID: 28486510 PMCID: PMC5423648 DOI: 10.1371/journal.pone.0177270] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 04/25/2017] [Indexed: 11/18/2022] Open
Abstract
The transfer of an acetyl group from acetyl-CoA to an acceptor amine is a ubiquitous biochemical transformation catalyzed by Gcn5-related N-acetyltransferases (GNATs). Although it is established that the reaction proceeds through a sequential ordered mechanism, the role of the acetyl group in driving the ordered formation of binary and ternary complexes remains elusive. Herein, we show that CoA and acetyl-CoA alter the conformation of the substrate binding site of an arylalkylamine N-acetyltransferase (AANAT) to facilitate interaction with acceptor substrates. However, it is the presence of the acetyl group within the catalytic funnel that triggers high affinity binding. Acetyl group occupancy is relayed through a conserved salt bridge between the P-loop and the acceptor binding site, and is manifested as differential dynamics in the CoA and acetyl-CoA-bound states. The capacity of the acetyl group carried by an acceptor to promote its tight binding even in the absence of CoA, but also its mutually exclusive position to the acetyl group of acetyl-CoA underscore its importance in coordinating the progression of the catalytic cycle.
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Affiliation(s)
- Adam A. Aboalroub
- Department of Chemistry, University of South Florida, Tampa, Florida, United States of America
| | - Ashleigh B. Bachman
- Department of Chemistry, University of South Florida, Tampa, Florida, United States of America
| | - Ziming Zhang
- Department of Chemistry, University of South Florida, Tampa, Florida, United States of America
| | - Dimitra Keramisanou
- Department of Chemistry, University of South Florida, Tampa, Florida, United States of America
| | - David J. Merkler
- Department of Chemistry, University of South Florida, Tampa, Florida, United States of America
| | - Ioannis Gelis
- Department of Chemistry, University of South Florida, Tampa, Florida, United States of America
- * E-mail:
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5
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Mori S, Nepal KK, Kelly GT, Sharma V, Simkhada D, Gowda V, Delgado D, Watanabe CMH. Priming of Azabicycle Biosynthesis in the Azinomycin Class of Antitumor Agents. Biochemistry 2017; 56:805-808. [PMID: 28135072 DOI: 10.1021/acs.biochem.6b01108] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The biosynthesis of the azabicyclic ring system of the azinomycin family of antitumor agents represents the "crown jewel" of the pathway and is a complex process involving at least 14 enzymatic steps. This study reports on the first biosynthetic step, the inroads, in the construction of the novel aziridino [1,2-a]pyrrolidine, azabicyclic core, allowing us to support a new mechanism for azabicycle formation.
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Affiliation(s)
- Shogo Mori
- Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
| | - Keshav K Nepal
- Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
| | - Gilbert T Kelly
- Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
| | - Vasudha Sharma
- Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
| | - Dinesh Simkhada
- Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
| | - Vishruth Gowda
- Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
| | - Dioscar Delgado
- Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
| | - Coran M H Watanabe
- Department of Chemistry, Texas A&M University , College Station, Texas 77843, United States
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6
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Qin Z, Xiao Y, Yang X, Mesters JR, Yang S, Jiang Z. A unique GCN5-related glucosamine N-acetyltransferase region exist in the fungal multi-domain glycoside hydrolase family 3 β-N-acetylglucosaminidase. Sci Rep 2015; 5:18292. [PMID: 26669854 PMCID: PMC4680927 DOI: 10.1038/srep18292] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 11/16/2015] [Indexed: 11/17/2022] Open
Abstract
Glycoside hydrolase (GH) family 3 β-N-acetylglucosaminidases widely exist in the filamentous fungi, which may play a key role in chitin metabolism of fungi. A multi-domain GH family 3 β-N-acetylglucosaminidase from Rhizomucor miehei (RmNag), exhibiting a potential N-acetyltransferase region, has been recently reported to show great potential in industrial applications. In this study, the crystal structure of RmNag was determined at 2.80 Å resolution. The three-dimensional structure of RmNag showed four distinctive domains, which belong to two distinguishable functional regions — a GH family 3 β-N-acetylglucosaminidase region (N-terminal) and a N-acetyltransferase region (C-terminal). From structural and functional analysis, the C-terminal region of RmNag was identified as a unique tandem array linking general control non-derepressible 5 (GCN5)-related N-acetyltransferase (GNAT), which displayed glucosamine N-acetyltransferase activity. Structural analysis of this glucosamine N-acetyltransferase region revealed that a unique glucosamine binding pocket is located in the pantetheine arm binding terminal region of the conserved CoA binding pocket, which is different from all known GNAT members. This is the first structural report of a glucosamine N-acetyltransferase, which provides novel structural information about substrate specificity of GNATs. The structural and functional features of this multi-domain β-N-acetylglucosaminidase could be useful in studying the catalytic mechanism of GH family 3 proteins.
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Affiliation(s)
- Zhen Qin
- College of Food Science and Nutritional Engineering, Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100083, China
| | - Yibei Xiao
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, Ratzeburger Allee 160, 23538, Lübeck, Germany
| | - Xinbin Yang
- College of Food Science and Nutritional Engineering, Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100083, China
| | - Jeroen R Mesters
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, Ratzeburger Allee 160, 23538, Lübeck, Germany
| | - Shaoqing Yang
- College of Food Science and Nutritional Engineering, Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100083, China
| | - Zhengqiang Jiang
- College of Food Science and Nutritional Engineering, Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing 100083, China
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7
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Rudolf JD, Bigelow L, Chang C, Cuff ME, Lohman JR, Chang CY, Ma M, Yang D, Clancy S, Babnigg G, Joachimiak A, Phillips GN, Shen B. Crystal Structure of the Zorbamycin-Binding Protein ZbmA, the Primary Self-Resistance Element in Streptomyces flavoviridis ATCC21892. Biochemistry 2015; 54:6842-51. [PMID: 26512730 DOI: 10.1021/acs.biochem.5b01008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The bleomycins (BLMs), tallysomycins (TLMs), phleomycin, and zorbamycin (ZBM) are members of the BLM family of glycopeptide-derived antitumor antibiotics. The BLM-producing Streptomyces verticillus ATCC15003 and the TLM-producing Streptoalloteichus hindustanus E465-94 ATCC31158 both possess at least two self-resistance elements, an N-acetyltransferase and a binding protein. The N-acetyltransferase provides resistance by disrupting the metal-binding domain of the antibiotic that is required for activity, while the binding protein confers resistance by sequestering the metal-bound antibiotic and preventing drug activation via molecular oxygen. We recently established that the ZBM producer, Streptomyces flavoviridis ATCC21892, lacks the N-acetyltransferase resistance gene and that the ZBM-binding protein, ZbmA, is sufficient to confer resistance in the producing strain. To investigate the resistance mechanism attributed to ZbmA, we determined the crystal structures of apo and Cu(II)-ZBM-bound ZbmA at high resolutions of 1.90 and 1.65 Å, respectively. A comparison and contrast with other structurally characterized members of the BLM-binding protein family revealed key differences in the protein-ligand binding environment that fine-tunes the ability of ZbmA to sequester metal-bound ZBM and supports drug sequestration as the primary resistance mechanism in the producing organisms of the BLM family of antitumor antibiotics.
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Affiliation(s)
- Jeffrey D Rudolf
- Department of Chemistry, The Scripps Research Institute , Jupiter, Florida 33458, United States
| | - Lance Bigelow
- Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - Changsoo Chang
- Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - Marianne E Cuff
- Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - Jeremy R Lohman
- Department of Chemistry, The Scripps Research Institute , Jupiter, Florida 33458, United States
| | - Chin-Yuan Chang
- Department of Chemistry, The Scripps Research Institute , Jupiter, Florida 33458, United States
| | - Ming Ma
- Department of Chemistry, The Scripps Research Institute , Jupiter, Florida 33458, United States
| | - Dong Yang
- Department of Chemistry, The Scripps Research Institute , Jupiter, Florida 33458, United States
| | - Shonda Clancy
- Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - Gyorgy Babnigg
- Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - Andrzej Joachimiak
- Midwest Center for Structural Genomics and Structural Biology Center, Biosciences Division, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - George N Phillips
- BioSciences at Rice and Department of Chemistry, Rice University , Houston, Texas 77251, United States
| | - Ben Shen
- Department of Chemistry, The Scripps Research Institute , Jupiter, Florida 33458, United States.,Department of Molecular Therapeutics, The Scripps Research Institute , Jupiter, Florida 33458, United States.,Natural Products Library Initiative, The Scripps Research Institute , Jupiter, Florida 33458, United States
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8
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Sugiyama M. Structural biological study of self-resistance determinants in antibiotic-producing actinomycetes. J Antibiot (Tokyo) 2015; 68:543-50. [PMID: 25873321 DOI: 10.1038/ja.2015.32] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Revised: 02/13/2015] [Accepted: 02/21/2015] [Indexed: 11/09/2022]
Abstract
As antibiotics act to inhibit the growth of bacteria, the drugs are useful for treating bacterial infectious diseases. However, microorganisms that produce antibiotics must be protected from the lethal effect of their own antibiotic product. In this review, the fruit of our group's current research on self-protection mechanisms of Streptomyces producing antibiotics that inhibit DNA, protein and bacterial cell wall syntheses will be described.
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Affiliation(s)
- Masanori Sugiyama
- Department of Molecular Microbiology and Biotechnology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
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9
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Jin S, Shi XJ, Sun XD, Wang SY, Wang GY. Sclerosing cholangitis secondary to bleomycin-iodinated embolization for liver hemangioma. World J Gastroenterol 2014; 20:17680-17685. [PMID: 25516686 PMCID: PMC4265633 DOI: 10.3748/wjg.v20.i46.17680] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Revised: 06/17/2014] [Accepted: 07/22/2014] [Indexed: 02/06/2023] Open
Abstract
Sclerosing cholangitis (SC) is a rarely reported morbidity secondary to transcatheter arterial chemoembolization (TACE) with bleomycin-iodinated oil (BIO) for liver cavernous hemangioma (LCH). This report retrospectively evaluated the diagnostic and therapeutic course of a patient with LDH who presented obstructive jaundice 6 years after TACE with BIO. Preoperative imaging identified a suspected malignant biliary stricture located at the convergence of the left and right hepatic ducts. Operative exploration demonstrated a full-thickness sclerosis of the hilar bile duct with right hepatic duct stricture and right lobe atrophy. Radical hepatic hilar resection with right-side hemihepatectomy and Roux-en-Y hepaticojejunostomy was performed because hilar cancer could not be excluded on frozen biopsy. Pathological results showed chronic pyogenic inflammation of the common and right hepatic ducts with SC in the portal area. Secondary SC is a long-term complication that may occur in LCH patients after TACE with BIO and must be differentiated from hilar malignancy. Hepatic duct plasty is a definitive but technically challenging treatment modality for secondary SC.
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MESH Headings
- Adult
- Anastomosis, Roux-en-Y
- Antibiotics, Antineoplastic/administration & dosage
- Antibiotics, Antineoplastic/adverse effects
- Bile Duct Neoplasms/diagnosis
- Biopsy
- Bleomycin/administration & dosage
- Bleomycin/adverse effects
- Chemoembolization, Therapeutic/adverse effects
- Cholangiopancreatography, Endoscopic Retrograde
- Cholangiopancreatography, Magnetic Resonance
- Cholangitis, Sclerosing/chemically induced
- Cholangitis, Sclerosing/diagnosis
- Cholangitis, Sclerosing/surgery
- Diagnosis, Differential
- Female
- Hemangioma, Cavernous/therapy
- Hepatectomy
- Humans
- Iodized Oil/adverse effects
- Jaundice, Obstructive/chemically induced
- Jejunostomy
- Liver Neoplasms/therapy
- Predictive Value of Tests
- Time Factors
- Tomography, X-Ray Computed
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10
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Coughlin JM, Rudolf JD, Wendt-Pienkowski E, Wang L, Unsin C, Galm U, Yang D, Tao M, Shen B. BlmB and TlmB provide resistance to the bleomycin family of antitumor antibiotics by N-acetylating metal-free bleomycin, tallysomycin, phleomycin, and zorbamycin. Biochemistry 2014; 53:6901-9. [PMID: 25299801 PMCID: PMC4230324 DOI: 10.1021/bi501121e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
The bleomycin (BLM) family of glycopeptide-derived
antitumor antibiotics
consists of BLMs, tallysomycins (TLMs), phleomycins (PLMs), and zorbamycin
(ZBM). The self-resistant elements BlmB and TlmB, discovered from
the BLM- and TLM-producing organisms Streptomyces verticillus ATCC15003 and Streptoalloteichus hindustanus E465-94
ATCC31158, respectively, are N-acetyltransferases
that provide resistance to the producers by disrupting the metal-binding
domain of the antibiotics required for activity. Although each member
of the BLM family of antibiotics possesses a conserved metal-binding
domain, the structural differences between each member, namely, the
bithiazole moiety and C-terminal amine of BLMs, have been suggested
to instill substrate specificity within BlmB. Here we report that
BlmB and TlmB readily accept and acetylate BLMs, TLMs, PLMs, and ZBM in vitro but only in the metal-free forms. Kinetic analysis
of BlmB and TlmB reveals there is no strong preference or rate enhancement
for specific substrates, indicating that the structural differences
between each member of the BLM family play a negligible role in substrate
recognition, binding, or catalysis. Intriguingly, the zbm gene cluster from Streptomyces flavoviridis ATCC21892
does not contain an N-acetyltransferase, yet ZBM
is readily acetylated by BlmB and TlmB. We subsequently established
that S. flavoviridis lacks the homologue of BlmB
and TlmB, and ZbmA, the ZBM-binding protein, alone is sufficient to
provide ZBM resistance. We further confirmed that BlmB can indeed
confer resistance to ZBM in vivo in S. flavoviridis, introduction of which into wild-type S. flavoviridis further increases the level of resistance.
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Affiliation(s)
- Jane M Coughlin
- Division of Pharmaceutical Sciences, University of Wisconsin-Madison , Madison, Wisconsin 53705, United States
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11
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Saini J, Bansal V, Chandra A, Madan J, Jain UK, Chandra R, Jain SM. Bleomycin sulphate loaded nanostructured lipid particles augment oral bioavailability, cytotoxicity and apoptosis in cervical cancer cells. Colloids Surf B Biointerfaces 2014; 118:101-10. [PMID: 24732397 DOI: 10.1016/j.colsurfb.2014.03.036] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 03/15/2014] [Accepted: 03/23/2014] [Indexed: 11/25/2022]
Abstract
In present investigation, bleomycin sulphate loaded nanostructured lipid particles (BLM-NLPs) were constructed to enhance the oral bioavailability by overwhelming the first pass hepatic metabolism. The particles size and nanoencapsulation efficiency of BLM-NLPs were measured to be 17.4±5.4nm and 45.3±3.4%, respectively. Our studies indicated that the drug was molecularly dispersed in the lipid nanocoacervates, with amorphous geometry, without altering the chemical structure, as ascertained by spectral studies. The nanoformulation, BLM-NLPs was analyzed for dissolution testing, cytotoxicity, apoptosis and cellular uptake in human cervical cancer cell line, HeLa cells. BLM-NLPs released the drug with first order kinetic in simulated intestinal fluid (pH∼6.8±0.1), characterized by initial burst and followed by slow release. Further, an enhanced cytotoxicity (∼5.6 fold lower IC50), improved intracellular concentration (∼4.38 fold) and greater degree of apoptosis was induced by BLM-NLPs in HeLa cells, as compared to BLM alone. Moreover, BLM-NLPs also showed dose-dependent internalization, as evinced by cellular uptake study. The in vivo study indicated a significantly (P<0.0001) smaller elimination rate constant (KE), volume of distribution (Vd) and clearance rate (CLTotal) for BLM-NLPs, as compared to BLM solution in post-oral administrations. This clearly depicts the retention and stability of tailored nanoformulation in intestinal absorption pathway. In addition, our nanoformulation, BLM-NLPs documented significantly (P<0.0001)∼3.4 fold (66.20±2.57%) higher bioavailability than BLM solution (19.56±0.79%). In conclusion, our in vitro and in vivo results warrant the safety, efficacy and potency of tailored nanoformulation in clinical settings.
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Affiliation(s)
- Jyoti Saini
- Department of Pharmaceutics, Chandigarh College of Pharmacy, Mohali 140307, Punjab, India
| | - Vikas Bansal
- Department of Pharmaceutics, Chandigarh College of Pharmacy, Mohali 140307, Punjab, India
| | - Ankush Chandra
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Jitender Madan
- Department of Pharmaceutics, Chandigarh College of Pharmacy, Mohali 140307, Punjab, India.
| | - Upendra Kumar Jain
- Department of Pharmaceutics, Chandigarh College of Pharmacy, Mohali 140307, Punjab, India
| | - Ramesh Chandra
- Dr. B.R Ambedkar Centre for Biomedical Research, University of Delhi, Delhi 110007, India
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12
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Tang X, Gross M, Xie Y, Kulik A, Gust B. Identification of Mureidomycin Analogues and Functional Analysis of an N-Acetyltransferase in Napsamycin Biosynthesis. Chembiochem 2013; 14:2248-55. [DOI: 10.1002/cbic.201300287] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Indexed: 11/05/2022]
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13
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Filippova EV, Shuvalova L, Minasov G, Kiryukhina O, Zhang Y, Clancy S, Radhakrishnan I, Joachimiak A, Anderson WF. Crystal structure of the novel PaiA N-acetyltransferase from Thermoplasma acidophilum involved in the negative control of sporulation and degradative enzyme production. Proteins 2011; 79:2566-77. [PMID: 21633970 DOI: 10.1002/prot.23062] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Revised: 03/28/2011] [Accepted: 03/31/2011] [Indexed: 11/07/2022]
Abstract
GCN5-related N-acetyltransferases (GNATs) are the most widely distributed acetyltransferase systems among all three domains of life. GNATs appear to be involved in several key processes, including microbial antibiotic resistance, compacting eukaryotic DNA, controlling gene expression, and protein synthesis. Here, we report the crystal structure of a putative GNAT Ta0374 from Thermoplasma acidophilum, a hyperacidophilic bacterium, that has been determined in an apo-form, in complex with its natural ligand (acetyl coenzyme A), and in complex with a product of reaction (coenzyme A) obtained by cocrystallization with spermidine. Sequence and structural analysis reveals that Ta0374 belongs to a novel protein family, PaiA, involved in the negative control of sporulation and degradative enzyme production. The crystal structure of Ta0374 confirms that it binds acetyl coenzyme A in a way similar to other GNATs and is capable of acetylating spermidine. Based on structural and docking analysis, it is expected that Glu53 and Tyr93 are key residues for recognizing spermidine. Additionally, we find that the purification His-Tag in the apo-form structure of Ta0374 prevents binding of acetyl coenzyme A in the crystal, though not in solution, and affects a chain-flip rotation of "motif A" which is the most conserved sequence among canonical acetyltransferases.
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Affiliation(s)
- E V Filippova
- Department of Molecular Pharmacology and Biological Chemistry, Northwestern University, Feinberg School of Medicine, Chicago, Illinois 60611, USA
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14
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Abstract
Bioactive natural products often possess uniquely functionalized structures with unusual modes of action; however, the natural product itself is not always the active species. We discuss molecules that draw on protecting group chemistry or else require activation to unmask reactive centers, illustrating that nature is not only a source of complex structures but also a guide for elegant chemical transformations which provides ingenious chemical solutions for drug delivery.
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Affiliation(s)
| | - Hendrik Luesch
- Department of Medicinal Chemistry, University of Florida, 1600 SW Archer Road, Gainesville, FL 32610, USA
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