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Velkova L, Todorov D, Dimitrov I, Shishkov S, Beeumen JV, Dolashka-Angelova P. Rapana Venosa Hemocyanin with Antiviral Activity. BIOTECHNOL BIOTEC EQ 2014. [DOI: 10.1080/13102818.2009.10818498] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Anteunis M, van Beeumen J, De Bruyn A, De Ley J. NMR Experiments On Acetals. XIX. The NMR Analysis and Structure of 3-Keto-Lactose and β-d-Galactose. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/bscb.19690781109] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Zervosen A, Valladares MH, Devreese B, Prosperi-Meys C, Adolph HW, Mercuri PS, Vanhove M, Amicosante G, van Beeumen J, Frère JM, Galleni M. Inactivation of Aeromonas hydrophila metallo-beta-lactamase by cephamycins and moxalactam. Eur J Biochem 2001; 268:3840-50. [PMID: 11432752 DOI: 10.1046/j.1432-1327.2001.02298.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Incubation of moxalactam and cefoxitin with the Aeromonas hydrophila metallo-beta-lactamase CphA leads to enzyme-catalyzed hydrolysis of both compounds and to irreversible inactivation of the enzyme by the reaction products. As shown by electrospray mass spectrometry, the inactivation of CphA by cefoxitin and moxalactam is accompanied by the formation of stable adducts with mass increases of 445 and 111 Da, respectively. The single thiol group of the inactivated enzyme is no longer titrable, and dithiothreitol treatment of the complexes partially restores the catalytic activity. The mechanism of inactivation by moxalactam was studied in detail. Hydrolysis of moxalactam is followed by elimination of the 3' leaving group (5-mercapto-1-methyltetrazole), which forms a disulfide bond with the cysteine residue of CphA located in the active site. Interestingly, this reaction is catalyzed by cacodylate.
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Affiliation(s)
- A Zervosen
- Centre for Protein Engineering, University of Liège, Belgium
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Mercuri PS, Bouillenne F, Boschi L, Lamotte-Brasseur J, Amicosante G, Devreese B, van Beeumen J, Frère JM, Rossolini GM, Galleni M. Biochemical characterization of the FEZ-1 metallo-beta-lactamase of Legionella gormanii ATCC 33297T produced in Escherichia coli. Antimicrob Agents Chemother 2001; 45:1254-62. [PMID: 11257043 PMCID: PMC90452 DOI: 10.1128/aac.45.4.1254-1262.2001] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The bla(FEZ-1) gene coding for the metallo-beta-lactamase of Legionella (Fluoribacter) gormanii ATCC 33297T was overexpressed via a T7 expression system in Escherichia coli BL21(DE3)(pLysS). The product was purified to homogeneity in two steps with a yield of 53%. The FEZ-1 metallo-beta-lactamase exhibited a broad-spectrum activity profile, with a preference for cephalosporins such as cephalothin, cefuroxime, and cefotaxime. Monobactams were not hydrolyzed. The beta-lactamase was inhibited by metal chelators. FEZ-1 is a monomeric enzyme with a molecular mass of 29,440 Da which possesses two zinc-binding sites. Its zinc content did not vary in the pH range of 5 to 9, but the presence of zinc ions modified the catalytic efficiency of the enzyme. A model of the FEZ-1 three-dimensional structure was built.
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Affiliation(s)
- P S Mercuri
- Centre d'Ingénierie des Protéines, Université de Liège, B-4000 Liège, Belgium
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Kostanjevecki V, Brigé A, Meyer TE, Cusanovich MA, Guisez Y, van Beeumen J. A membrane-bound flavocytochrome c-sulfide dehydrogenase from the purple phototrophic sulfur bacterium Ectothiorhodospira vacuolata. J Bacteriol 2000; 182:3097-103. [PMID: 10809687 PMCID: PMC94494 DOI: 10.1128/jb.182.11.3097-3103.2000] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [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] [Received: 11/24/1999] [Accepted: 03/03/2000] [Indexed: 11/20/2022] Open
Abstract
The amino acid sequence of Ectothiorhodospira vacuolata cytochrome c-552, isolated from membranes with n-butanol, shows that it is a protein of 77 amino acid residues with a molecular mass of 9,041 Da. It is closely related to the cytochrome subunit of Chlorobium limicola f. sp. thiosulfatophilum flavocytochrome c-sulfide dehydrogenase (FCSD), having 49% identity. These data allowed isolation of a 5.5-kb subgenomic clone which contains the cytochrome gene and an adjacent flavoprotein gene as in other species which have an FCSD. The cytochrome subunit has a signal peptide with a normal cleavage site, but the flavoprotein subunit has a signal sequence which suggests that the mature protein has an N-terminal cysteine, characteristic of a diacyl glycerol-modified lipoprotein. The membrane localization of FCSD was confirmed by Western blotting with antibodies raised against Chromatium vinosum FCSD. When aligned according to the three-dimensional structure of Chromatium FCSD, all but one of the side chains near the flavin are conserved. These include the Cys 42 flavin adenine dinucleotide binding site; the Cys 161-Cys 337 disulfide; Glu 167, which modulates the reactivity with sulfite; and aromatic residues which may function as charge transfer acceptors from the flavin-sulfite adduct (C. vinosum numbering). The genetic context of FCSD is different from that in other species in that flanking genes are not conserved. The transcript is only large enough to encode the two FCSD subunits. Furthermore, Northern hybridization showed that the production of E. vacuolata FCSD mRNA is regulated by sulfide. All cultures that contained sulfide in the medium had elevated levels of FCSD RNA compared with cells grown on organics (acetate, malate, or succinate) or thiosulfate alone, consistent with the role of FCSD in sulfide oxidation.
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Affiliation(s)
- V Kostanjevecki
- Laboratory for Protein Biochemistry and Protein Engineering, University of Ghent, 9000 Ghent, Belgium
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Tsakalidou E, Anastasiou R, Vandenberghe I, van Beeumen J, Kalantzopoulos G. Cell-wall-bound proteinase of Lactobacillus delbrueckii subsp. lactis ACA-DC 178: characterization and specificity for beta-casein. Appl Environ Microbiol 1999; 65:2035-40. [PMID: 10223997 PMCID: PMC91294 DOI: 10.1128/aem.65.5.2035-2040.1999] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/1998] [Accepted: 02/12/1999] [Indexed: 11/20/2022] Open
Abstract
Lactobacillus delbrueckii subsp. lactis ACA-DC 178, which was isolated from Greek Kasseri cheese, produces a cell-wall-bound proteinase. The proteinase was removed from the cell envelope by washing the cells with a Ca2+-free buffer. The crude proteinase extract shows its highest activity at pH 6.0 and 40 degrees C. It is inhibited by phenylmethylsulfonyl fluoride, showing that the enzyme is a serine-type proteinase. Considering the substrate specificity, the enzyme is similar to the lactococcal PI-type proteinases, since it hydrolyzes beta-casein mainly and alpha- and kappa-caseins to a much lesser extent. The cell-wall-bound proteinase from L. delbrueckii subsp. lactis ACA-DC 178 liberates four main peptides from beta-casein, which have been identified.
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Affiliation(s)
- E Tsakalidou
- Laboratory of Dairy Research, Department of Food Science and Technology, Agricultural University of Athens, 118 55 Athens, Greece
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Klarskov K, Piens K, Ståhlberg J, Høj PB, Beeumen JV, Claeyssens M. Cellobiohydrolase I from Trichoderma reesei: identification of an active-site nucleophile and additional information on sequence including the glycosylation pattern of the core protein. Carbohydr Res 1997; 304:143-54. [PMID: 9449766 DOI: 10.1016/s0008-6215(97)00215-2] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
(R,S)-3,4-Epoxybutyl beta-cellobioside, but not the corresponding propyl and pentyl derivatives, inactivates specifically and irreversibly cellobiohydrolase I from Trichoderma reesei by covalent modification of Glu212, the putative active-site nucleophile. The position and identity of the modified amino acid residue were determined using a combination of comparative liquid chromatography coupled on-line to electrospray ionization mass spectrometry, tandem mass spectrometry and microsequencing. It was found that the core protein corresponds to the N-terminal sequence pyrGlu1-Gly434 (Gly435) of intact cellobiohydrolase I. In the particular enzyme samples investigated, the asparagine residues in positions 45, 270 and 384 are each linked to a single 2-acetamido-2-deoxy-D-glucopyranose residue.
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Affiliation(s)
- K Klarskov
- Department of Biochemistry, Physiology and Microbiology, University of Gent, Belgium
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Abstract
The origin of tumor stroma hyaluronectin (HN), a glycoprotein that binds to hyaluronan (HA), has long remained unknown. Histological observations of human tumors suggest that tumor HN could originate from stroma fibroblasts, and in some cases from inflammatory cells. The fibroblast origin was confirmed by the discovery of HN-like antigen along with hyaluronan in culture medium of tumor-derived fibroblasts. An HA-binding protein was characterized in the culture medium of peripheral blood mononuclear cells (PBMC) in both normal subjects and tumor-bearing patients and was found to be human HN. Cultivated monocytes did not produce HA. HN was not related to the HA-binding site CD44. Sequencing of brain HN-derived peptides demonstrated that each determined peptide sequence was similar to a sequence of the proteoglycan PG-M/versican, suggesting that HN is the HA-binding moiety of the proteoglycan. One probe was synthesized from human PBMC by polymerase chain reaction with primers derived from HN sequences also found in versican. Northern blots were positive only with HN-producing cells. The main RNAs were in the 6-8 kb range, and there was a limited proportion of smaller RNA, which was compatible with the size expected from the HN molecular mass. Southern blotting of monocytes and tumor cells demonstrated that the gene was limited to a unique band. We conclude that HN, an extracellular component of brain, connective embryonic, inflammatory and tumoral tissues, is a PG-M/versican-derived molecule. Our results suggest that tumor HN, which originates from fibroblasts and monocytes of tumor stroma, is a molecular component of the host-tumor relationship and could play a role in the regulation of HA activity in oncogenesis.
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Affiliation(s)
- B Delpech
- Laboratoire d'Oncologie Moléculaire, Centre Henri-Becquerel, Rouen, France
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Mukherjee T, Basu D, Mahapatra S, Goffin C, van Beeumen J, Basu J. Biochemical characterization of the 49 kDa penicillin-binding protein of Mycobacterium smegmatis. Biochem J 1996; 320 ( Pt 1):197-200. [PMID: 8947487 PMCID: PMC1217917 DOI: 10.1042/bj3200197] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The 49 kDa penicillin-binding protein (PBP) of Mycobacterium smegmatis catalyses the hydrolysis of the peptide or S-ester bond of carbonyl donors R1-CONH-CHR2-COX-CHR2-COO- (where X is NH or S). In the presence of a suitable amino acceptor, the reaction partitions between the transpeptidation and hydrolysis pathways, with the amino acceptor, behaving as a simple alternative nucleophile at the level of the acyl-enzyme. By virtue of its N-terminal sequence similarity, the 49 kDa PBP represents one of the class of monofunctional low-molecular-mass PBPs. An immunologically related protein of M(r) 52,000 is present in M. tuberculosis. The 49 kDa PBP is sensitive towards amoxycillin, imipenem, flomoxef and cefoxitin.
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Affiliation(s)
- T Mukherjee
- Department of Chemistry, Bose Institute, Calcutta, India
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van Driessche G, Dennison C, Sykes AG, van Beeumen J. Heterogeneity of the covalent structure of the blue copper protein umecyanin from horseradish roots. Protein Sci 1995; 4:209-27. [PMID: 7757010 PMCID: PMC2143053 DOI: 10.1002/pro.5560040208] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The covalent structure of umecyanin has been determined by a combination of classical Edman degradation sequence analysis and plasma desorption, laser desorption, and electrospray ionization mass spectrometry. The preparation appeared to contain two isoforms having either a valine (75%) or an isoleucine (25%) residue at position 48. The polypeptide chain of 115 amino acids is strongly heterogeneous at its C-terminal end as a result of proteolytic cleavages at several places within the last 10 residues. The major fraction of the umecyanin preparation is only 106 residues long. The C-terminal tail 107-115 contains mainly alanine and glycine residues and a single hydroxyproline residue. In the native protein there is a disulfide bridge between Cys 91 and Cys 57, but in the apoprotein there is a disulfide shift that involves Cys 91 and one of the four copper binding residues (Cys 85). The three other ligand binding residues are His 44, His 90, and Gln 95. This tetrad of amino acids is the same as occurs in other type 1 copper proteins from plants such as cucumber peeling cupredoxin and lacquer tree stellacyanin. The umecyanin isoforms are glycoproteins with a glycan core having the same carbohydrate composition as that of horseradish peroxidase, a fact that is convincingly supported thanks to the high accuracy of the electrospray mass spectrometric technique. We suggest that the glycan may play a role in the association of the protein to the cellular membrane, but the precise functional role of umecyanin remains to be determined. We also discuss the evolutionary position of umecyanin in relation to the type 1 copper proteins in general.
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Affiliation(s)
- G van Driessche
- Department of Biochemistry, Physiology and Microbiology, University of Gent, Belgium
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Becuwe P, van Beeumen J, Samyn B, Touzel JP, Slomianny C, Camus D, Dive D. Purification, characterization and amino terminal sequence of the superoxide dismutase from Babesia hylomysci. Comp Biochem Physiol B Biochem Mol Biol 1994; 109:637-45. [PMID: 7881825 DOI: 10.1016/0305-0491(94)90126-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Babesia hylomysci was found to contain two superoxide dismutase (SOD) isoenzymes with isoelectric points (pI) of 4.9 and 5.2. The two isoenzymes (45 and 47 kDa) were composed of two subunits of 22 kDa. An unique amino terminal sequence was determined up to 34 residues from the pooled isoenzymes and was identified as a sequence of SOD. The comparison of this N-terminal sequence of B. hylomysci SOD with 29 known Fe- or Mn-SODs showed more homologies with Fe-SODs.
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Affiliation(s)
- P Becuwe
- INSERM U42, Villeneuve d'Ascq, France
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Hoff WD, Düx P, Hård K, Devreese B, Nugteren-Roodzant IM, Crielaard W, Boelens R, Kaptein R, van Beeumen J, Hellingwerf KJ. Thiol ester-linked p-coumaric acid as a new photoactive prosthetic group in a protein with rhodopsin-like photochemistry. Biochemistry 1994; 33:13959-62. [PMID: 7947803 DOI: 10.1021/bi00251a001] [Citation(s) in RCA: 211] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A number of Eubacteria contain a photoactive yellow protein which has a photosensory function in negative phototaxis. It has been proposed that the cofactor responsible for the intense yellow color of this protein is retinal [McRee, D. E., et al. (1989) Proc. Natl. Acad. Sci. U.S.A. 86, 6533-6537]. This would make it the first eubacterial rhodopsin. Here we report the chemical structure of this chromophoric group to be p-coumaric acid, which is covalently bound to a unique cysteine in the apoprotein via a thiol ester bond, and thus not retinal. This makes PYP the first example of a protein containing p-coumaric acid, a metabolite previously found only in plants, as a prosthetic group and establishes the photoactive yellow proteins as a new type of photochemically active receptor molecule.
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Affiliation(s)
- W D Hoff
- Department of Microbiology, E. C. Slater Institute, University of Amsterdam, The Netherlands
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Mahapatra S, Basu J, van Beeumen J, Kundu M. Characterization of a 38 kDa penicillin-binding protein and its possible involvement in maintaining stationary-phase cells of Shigella dysenteriae. Microbiology (Reading) 1994; 140 ( Pt 11):3177-82. [PMID: 7812457 DOI: 10.1099/13500872-140-11-3177] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
This paper reports the first attempt to characterize the penicillin-binding proteins (PBPs) of Shigella dysenteriae, an important human pathogen. The PBP pattern of the membranes of S. dysenteriae closely resembles that of Escherichia coli membranes. A 38 kDa PBP which is an important target for the penem SCH34343, the cephamycin cefoxitin and the oxacephem moxalactam, has been purified. This PBP is immunologically related to a PBP of similar molecular mass in E. coli and is present at high levels in stationary-phase cells of S. dysenteriae.
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Affiliation(s)
- S Mahapatra
- Department of Chemistry, Bose Institute, Calcutta, India
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Huitema F, van Beeumen J, van Driessche G, Duine JA, Canters GW. Cloning and sequencing of the gene coding for the large subunit of methylamine dehydrogenase from Thiobacillus versutus. J Bacteriol 1993; 175:6254-9. [PMID: 8407797 PMCID: PMC206721 DOI: 10.1128/jb.175.19.6254-6259.1993] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The gene that codes for the alpha-subunit of methylamine dehydrogenase from Thiobacillus versutus, madA, was cloned and sequenced. It codes for a protein of 395 amino acids preceded by a leader sequence of 31 amino acids. The derived amino acid sequence was confirmed by partial amino acid sequencing. The start of the mature protein could not be determined by direct sequencing, since the N terminus appeared to be blocked. Instead, it was determined by electrospray mass spectrometry. Confirmation of the results was obtained by sequencing the N terminus after pyroglutamate aminopeptidase digestion. The sequence is homologous to the Paracoccus denitrificans nucleotide sequence. A second open reading frame, called open reading frame 3, is located immediately downstream of madA.
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Affiliation(s)
- F Huitema
- Gorlaeus Laboratories, Leiden University, The Netherlands
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Walreavens V, Jaziri M, van Beeumen J, Schnek AG, Kleinschmidt T, Looze Y. Isolation and preliminary characterization of the cysteine-proteinases from the latex of Carica candamarcensis Hook. Biol Chem Hoppe Seyler 1993; 374:501-6. [PMID: 8216902 DOI: 10.1515/bchm3.1993.374.7-12.501] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The cysteine-proteinase chymopapain from Carica papaya L. is used for chemonucleolysis of damaged human intervertebral spinal discs. The purification of this enzyme is difficult. To overcome these problems, we were looking for a substitute among the cysteine-proteinases of Carica candamarcensis Hook. The latex from unripe fruits was collected in an aqueous solution of methylethanethiolsulfonate to prevent proteolytic activities. The soluble fraction of the lypophilized product provided four enzymatically active peaks (CC-I-CC-IV) during chromatography on CM-Sephadex C-50 in sodium acetate buffer, pH5.0. They could be further purified by rechromatography under similar conditions. The isolated enzymes have been characterized by PAGE, analysis of the Fourier transform infrared spectra, preliminary studies of their specificities as well as a comparison of the N-terminal amino-acid sequences up to position 43. CC-III proved to be glycosylated. CC-I and CC-III from Carica candamarcensis Hook are suggested to correspond to papain and chymopapain from Carica papaya L., respectively.
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Affiliation(s)
- V Walreavens
- Protein Chemistry Unit, Faculty of Medicine, University of Brussels, Belgium
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Bystrykh LV, Vonck J, van Bruggen EF, van Beeumen J, Samyn B, Govorukhina NI, Arfman N, Duine JA, Dijkhuizen L. Electron microscopic analysis and structural characterization of novel NADP(H)-containing methanol: N,N'-dimethyl-4-nitrosoaniline oxidoreductases from the gram-positive methylotrophic bacteria Amycolatopsis methanolica and Mycobacterium gastri MB19. J Bacteriol 1993; 175:1814-22. [PMID: 8449887 PMCID: PMC203978 DOI: 10.1128/jb.175.6.1814-1822.1993] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The quaternary protein structure of two methanol:N,N'-dimethyl-4-nitrosoaniline (NDMA) oxidoreductases purified from Amycolatopsis methanolica and Mycobacterium gastri MB19 was analyzed by electron microscopy and image processing. The enzymes are decameric proteins (displaying fivefold symmetry) with estimated molecular masses of 490 to 500 kDa based on their subunit molecular masses of 49 to 50 kDa. Both methanol:NDMA oxidoreductases possess a tightly but noncovalently bound NADP(H) cofactor at an NADPH-to-subunit molar ratio of 0.7. These cofactors are redox active toward alcohol and aldehyde substrates. Both enzymes contain significant amounts of Zn2+ and Mg2+ ions. The primary amino acid sequences of the A. methanolica and M. gastri MB19 methanol:NDMA oxidoreductases share a high degree of identity, as indicated by N-terminal sequence analysis (63% identity among the first 27 N-terminal amino acids), internal peptide sequence analysis, and overall amino acid composition. The amino acid sequence analysis also revealed significant similarity to a decameric methanol dehydrogenase of Bacillus methanolicus C1.
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Affiliation(s)
- L V Bystrykh
- Department of Microbiology, University of Groningen, Haren, The Netherlands
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20
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Macarron R, van Beeumen J, Henrissat B, de la Mata I, Claeyssens M. Identification of an essential glutamate residue in the active site of endoglucanase III from Trichoderma reesei. FEBS Lett 1993; 316:137-40. [PMID: 8093602 DOI: 10.1016/0014-5793(93)81202-b] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
n-Propyl, n-butyl and n-pentyl beta-cellobiosides with a reactive omega-epoxide in their aglycon completely and irreversibly inactivate endoglucanase III from Trichoderma reesei. The pentyl derivative was found to be most effective. From these affinity labeling experiments evidence was found for the implication of Glu329 in the reaction mechanism. This is discussed in relation to other structural/functional data known for endoglucanase III and several other family A glycanases.
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Affiliation(s)
- R Macarron
- Departamento de Bioquimica, Facultad de Ciencias Biologicas, Universidad Complutense, Madrid, Spain
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21
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Wisselaar HA, Kroos MA, Hermans MM, van Beeumen J, Reuser AJ. Structural and functional changes of lysosomal acid alpha-glucosidase during intracellular transport and maturation. J Biol Chem 1993; 268:2223-31. [PMID: 8420990] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The synthesis and posttranslational modification of lysosomal acid alpha-glucosidase were studied in a cell-free translation system and in mammalian cells transfected with acid alpha-glucosidase cDNA constructs. The newly synthesized precursor, sequestered in the endoplasmic reticulum, was demonstrated to be membrane-bound by lack of signal peptide cleavage, and to be catalytically inactive. Sugar chain modification was shown to occur in the Golgi complex and to be dependent on the rate of transport. From the trans-Golgi network different routes were found to be followed by acid alpha-glucosidase. A fraction of precursor molecules, proteolytically released from the membrane anchor, appeared to enter the secretory pathway and was recovered from the cell culture medium in a catalytically active form. A second fraction was transported to the lysosomes and was trimmed in a stepwise process at both the amino- and carboxyl-terminal ends. The intramolecular cleavage sites were determined. Involvement of thiol proteinases was demonstrated. Specificity for the natural substrate glycogen was gained during the maturation process. The phosphomannosyl receptor is assumed to be instrumental in the lysosomal targeting of acid alpha-glucosidase, but a phosphomannosyl receptor-independent transport of membrane-bound precursor molecules to the lysosomes, either directly or via the plasma membrane, cannot be excluded.
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Affiliation(s)
- H A Wisselaar
- Department of Cell Biology and Genetics, Erasmus University, Rotterdam, The Netherlands
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22
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Wisselaar H, Kroos M, Hermans M, van Beeumen J, Reuser A. Structural and functional changes of lysosomal acid alpha-glucosidase during intracellular transport and maturation. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(18)53985-5] [Citation(s) in RCA: 125] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Tomme P, van Beeumen J, Claeyssens M. Modification of catalytically important carboxy residues in endoglucanase D from Clostridium thermocellum. Biochem J 1992; 285 ( Pt 1):319-24. [PMID: 1637316 PMCID: PMC1132783 DOI: 10.1042/bj2850319] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Endoglucanase D (EC 3.2.1.4; EGD) from Clostridium thermocellum is rapidly (k = 216 M-1.min-1) and almost completely (greater than 95%) inactivated with Woodward's reagent K (N-ethyl-5-phenylisoxazolium-3'-sulphonate). Spectrophotometric analysis at 340 nm reveals that eight carboxy residues react, whereas specific ligands protect one residue against modification. The enzyme retains it full activity under the latter conditions. The kinetics and pH-dependence of inactivation point towards the involvement of one or more essential carboxy groups with a pKa of 5.7-5.8. Samples modified in the absence or presence of ligand were analysed by reversed-phase liquid chromatography after proteolysis with subtilisin. Dual-wavelength monitoring at 214 and 340 nm during this fractionation leads to the identification of a putatively active-site peptide (Gly-508-Ala-562) which was further characterized by amino acid and partial N-terminal sequence analyses. Asp-546 and Glu-555 are postulated as possible active-site residues. This follows from alignments using ten endoglucanase sequences belonging to the same family. Strong local conservation suggests that this C-terminal sequence is structurally and/or functionally important.
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Affiliation(s)
- P Tomme
- Laboratorium voor Biochemie, Rijksuniversiteit Gent, Belgium
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24
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Hermans MM, Kroos MA, van Beeumen J, Oostra BA, Reuser AJ. Human lysosomal alpha-glucosidase. Characterization of the catalytic site. J Biol Chem 1991; 266:13507-12. [PMID: 1856189] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The substrate analogue conduritol B epoxide (CBE) is demonstrated to be an active site-directed inhibitor of human lysosomal alpha-glucosidase. A competitive mode of inhibition is obtained with glycogen as natural and 4-methylumbelliferyl-alpha-D-glucopyranoside as artificial substrate. The inactivation of the enzyme is time and concentration dependent and results in the covalent binding of CBE. Catalytic activity is required for binding to occur. CBE-labeled peptides containing the catalytic residue of lysosomal alpha-glucosidase were isolated and identified by microsequencing and amino acid analysis. The peptides appeared to originate from a protein domain which is highly conserved among alpha-amylases, maltase, glucoamylases, and transglucanosylases. Based on the sequence similarity and the mechanism of CBE binding, Asp-518 is predicted to be the essential carboxylate in the active site of lysosomal alpha-glucosidase. The functional importance of Asp-518 and other residues around the catalytic site was studied by expression of in vitro mutagenized alpha-glucosidase cDNA in transiently transfected COS cells. Substitution of Asp-513 by Glu-513 is shown to interfere with the posttranslational modification and the intracellular transport of the alpha-glucosidase precursor. The residues Trp-516 and Asp-518 are demonstrated to be critical for catalytic function.
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Affiliation(s)
- M M Hermans
- Department of Cell Biology and Genetics, Erasmus University, Rotterdam, The Netherlands
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Franceschini N, Amicosante G, Perilli M, Maccarrone M, Oratore A, van Beeumen J, Frère JM. Proteolytic interconversion and N-terminal sequences of the Citrobacter diversus major beta-lactamases. Biochem J 1991; 275 ( Pt 3):629-33. [PMID: 2039443 PMCID: PMC1150101 DOI: 10.1042/bj2750629] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The N-terminal sequences of the two major beta-lactamases produced by Citrobacter diversus differed only by the absence of the first residue in form II and the loss of five amino acid residues at the C-terminal end. Limited proteolysis of the homogeneous form I protein yielded a variety of enzymatically active products. In the major product obtained after the action of papain, the first three N-terminal residues of form I had been cleaved, whereas at the C-terminal end the treated enzyme lacked five residues. However, this cannot explain the different behaviours of form I, form II and papain digestion product upon chromatofocusing. Form I, which was sequenced up to position 56, exhibited a very high degree of similarity with a Klebsiella oxytoca beta-lactamase. The determined sequence, which contained the active serine residue, demonstrated that the chromosome-encoded beta-lactamase of Citrobacter diversus belong to class A.
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Affiliation(s)
- N Franceschini
- Università degli Studi dell'Aquila, Dipartimento di Scienze e Tecnologie Biomediche e di Biometria, Italy
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27
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Piras G, el Kharroubi A, van Beeumen J, Coeme E, Coyette J, Ghuysen JM. Characterization of an Enterococcus hirae penicillin-binding protein 3 with low penicillin affinity. J Bacteriol 1990; 172:6856-62. [PMID: 2254261 PMCID: PMC210803 DOI: 10.1128/jb.172.12.6856-6862.1990] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Enterococcus hirae S185, a clinical isolate from swine intestine, exhibits a relatively high resistance to penicillin and contains two 77-kDa penicillin-binding proteins 3 of high (PBP 3s) and low (PBP 3r) affinity to penicillin, respectively. A laboratory mutant S185r has been obtained which overproduces PBP 3r and has a highly increased resistance to penicillin. Peptide fragments specifically produced by trypsin and SV8 protease digestions of PBP 3r were isolated, and the amino acid sequences of their amino terminal regions were determined. On the basis of these sequences, oligonucleotides were synthesized and used as primers to generate, by polymerization chain reaction, a 233-bp DNA fragment the sequence of which translated into a 73-amino-acid peptide segment of PBP 3r. These structural data led to the conclusion that the E. hirae PBP 3r and the methicillin-resistant staphylococcal PBP 2' are members of the same class of high-Mr PBPs. As shown by immunological tests, PBP 3r is not related to PBP 3s but, in contrast, is related to the 71-kDa PBP 5 of low penicillin affinity which is responsible for penicillin resistance in E. hirae ATCC 9790 and R40.
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Affiliation(s)
- G Piras
- Service de Microbiologie, Université de Liège, Sart Tilman, Belgium
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Lommen A, Ratsma A, Bijlsma N, Canters GW, van Wielink JE, Frank J, van Beeumen J. Isolation and characterization of cytochrome c550 from the methylamine-oxidizing electron-transport chain of Thiobacillus versutus. Eur J Biochem 1990; 192:653-61. [PMID: 2170127 DOI: 10.1111/j.1432-1033.1990.tb19272.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The isolation and purification of cytochrome c550 from the methylamine-oxidizing electron-transport chain in Thiobacillus versutus is reported. The cytochrome is a single-heme-containing type I cytochrome c with a relative molecular mass of 16 +/- 1 kDa, an isoelectric point of 4.6 +/- 0.1, a midpoint potential of 272 +/- 3 mV at pH less than 4 and 255 +/- 5 mV at pH = 7.0, and an axial coordination of the Fe by a methionine and a histidine. The midpoint potential decreases with increasing pH due to the deprotonation of a group tentatively identified as a propionate (pKa = 6.5 +/- 0.1 and 6.7 +/- 0.1 in the oxidized and reduced protein, respectively) and a change in the Fe coordination at pH greater than 10. The electron-self-exchange rate appears to depend strongly on the ionic strength of the solution and is relatively insensitive to changes in pH. At 313 K and pH 5.2 the electron-exchange rate amounts to 0.7 x 10(2) M-1 s-1 and 5.3 x 10(2) M-1 s-1 at I = 40 mM and I = 200 mM, respectively. Amino acid composition and molar absorption coefficients at various wavelengths are reported. Resonances of heme protons and the epsilon H3 group of the ligand methionine of the Fe have been identified in the 1H-NMR spectrum of the reduced as well as the oxidized cytochrome.
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Affiliation(s)
- A Lommen
- Gorlaeus Laboratories, Leiden University, The Netherlands
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Berghman LR, van Beeumen J, Decuypere E, Kühn ER, Vandesande F. One-step purification of chicken growth hormone from a crude pituitary extract by use of a monoclonal immunoadsorbent. J Endocrinol 1988; 118:381-7. [PMID: 3053959 DOI: 10.1677/joe.0.1180381] [Citation(s) in RCA: 68] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The immunization of mice with an affinity-purified glycoprotein preparation from chicken pituitary tissue yielded several monoclonal antibodies towards the recently described glycosylated variant of chicken GH. As all these antibodies recognize the classical (non-glycosylated) GH molecule equally well, they provide a suitable tool for the development of both a specific immunoadsorbent and an assay method. This paper deals with the surprising purification power of the immunoadsorbent that was produced with one of the monoclonal antibodies. The resulting preparation was more than 99% pure as assessed by reversed phase high-performance liquid chromatography and sodium dodecyl sulphate-polyacrylamide gel electrophoresis, so that no further purification steps were needed before the determination of the amino acid sequence of the material. The efficiency of the purification protocol as determined by a homologous, monoclonal antibody-based radioimmunoassay was virtually absolute. Moreover, the affinity-purified GH preparation was a mixture representing the multiple molecular forms of pituitary chicken GH, including both oligomeres and glycosylated GH. The purified preparations were finally used to demonstrate the hepatic 5'-monodeiodinase-stimulating activity of GH in the chicken embryo (results not shown), in order to prove that the biological activity of the molecule had not been damaged by elution from the immunoadsorbent.
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Affiliation(s)
- L R Berghman
- Laboratory for Neuroendocrinology and Immunological Biotechnology, Catholic University of Leuven, Belgium
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Lommen A, Canters GW, van Beeumen J. A 1H-NMR study on the blue copper protein amicyanin from Thiobacillus versutus. Resonance identifications, structural rearrangements and determination of the electron self-exchange rate constant. Eur J Biochem 1988; 176:213-23. [PMID: 3416870 DOI: 10.1111/j.1432-1033.1988.tb14271.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A number of resonances in the 1H-NMR spectra of reduced and oxidised amicyanin from Thiobacillus versutus have been identified by one- and two-dimensional NMR techniques. The second-order electron self-exchange rate constant (8.5 x 10(4) M-1.s-1; pH = 7.4; T = 308.5 K) was determined by measuring the line broadening of six singlets in slightly oxidised solutions of the protein. A large increase in electron exchange rate is observed in the presence of ferrocyanide. The copper atom in the reactive centre of the protein appears to be coordinated by nitrogens from two histidines and sulfurs from a methionine and a cysteine. One of the ligand histidines becomes protonated at low pH [pK*a = 6.74 (+/- 0.02)], the asterisk indicating value uncorrected for the deuterium isotope effect] in reduced amicyanin. This is the first example of a non-photosynthetic blue copper protein in which a ligand histidine becomes protonated at low pH. A small pH-independent conformational rearrangement occurs upon oxidation.
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Affiliation(s)
- A Lommen
- Gorlaeus Laboratories, Leiden University, The Netherlands
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Hoefsloot LH, Hoogeveen-Westerveld M, Kroos MA, van Beeumen J, Reuser AJ, Oostra BA. Primary structure and processing of lysosomal alpha-glucosidase; homology with the intestinal sucrase-isomaltase complex. EMBO J 1988; 7:1697-704. [PMID: 3049072 PMCID: PMC457155 DOI: 10.1002/j.1460-2075.1988.tb02998.x] [Citation(s) in RCA: 120] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Lysosomal alpha-glucosidase (acid maltase) is essential for degradation of glycogen in lysosomes. Enzyme deficiency results in glycogenosis type II. The amino acid sequence of the entire enzyme was derived from the nucleotide sequence of cloned cDNA. The cDNA comprises 3636 nt, and hybridizes with a messenger RNA of approximately 3.6 kb, which is absent in fibroblasts of two patients with glycogenosis type II. The encoded protein has a molecular mass of 104.645 kd and starts with a signal peptide. Sites of proteolytic processing are established by identification of N-terminal amino acid sequences of the 110-kd precursor, and the 76-kd and 70-kd mature forms of the enzyme encoded by the cDNA. Interestingly, both amino-terminal and carboxy-terminal processing occurs. Sites of sugar-chain attachment are proposed. A remarkable homology is observed between this soluble lysosomal alpha-glucosidase and the membrane-bound intestinal brush border sucrase-isomaltase enzyme complex. It is proposed that these enzymes are derived from the same ancestral gene. Around the putative active site of sucrase and isomaltase, 10 out of 13 amino acids are identical to the corresponding amino acids of lysosomal alpha-glucosidase. This strongly suggests that the aspartic acid residue at this position is essential for catalytic function of lysosomal alpha-glucosidase.
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Affiliation(s)
- L H Hoefsloot
- Department of Cell Biology and Genetics, Erasmus University, Rotterdam, The Netherlands
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Petratos K, Dauter Z, Wilson KS, Lommen A, van Beeumen J, Canters GW. Preliminary X-ray crystallographic study of amicyanin from Thiobacillus versutus. J Mol Biol 1988; 199:545-6. [PMID: 3351942 DOI: 10.1016/0022-2836(88)90626-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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van Damme J, de Ley M, van Beeumen J, Opdenakker G, Dayer JM, Billiau A, de Somer P. The Interferon-Inducing 22k Protein from Human Leucocytes: Amino Acid Sequence and Identity with Interleukin-1. Rheumatology (Oxford) 1985. [DOI: 10.1093/rheumatology/xxiv.suppl_1.72] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Joris B, Dusart J, Frere JM, van Beeumen J, Emanuel EL, Petursson S, Gagnon J, Waley SG. The active site of the P99 beta-lactamase from Enterobacter cloacae. Biochem J 1984; 223:271-4. [PMID: 6333871 PMCID: PMC1144291 DOI: 10.1042/bj2230271] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Labelling the beta-lactamase of Enterobacter cloacae P99 with a poor substrate or a mechanism-based inactivator points to an active-site serine residue in a sequence closely resembling that of the ampC beta-lactamase. These results establish the P99 enzyme as a class-C beta-lactamase, and the concurrence of the two approaches helps to confirm the reliability of determining active-site sequences with the aid of mechanism-based inactivators.
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35
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Tempst P, van Beeumen J. The complete amino-acid sequence of the low-spin class II cytochrome c-556 from Agrobacterium tumefaciens strain B2a. Eur J Biochem 1983; 129:603-14. [PMID: 6297889 DOI: 10.1111/j.1432-1033.1983.tb07091.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The amino acid sequence of the soluble monohaem cytochrome c-556 from Agrobacterium tumefaciens, strain B2a, has been determined. The sequence was derived from peptides obtained by digestion of the apoprotein with trypsin and chymotrypsin, and by subdigestion of some of the peptides with Staphylococcus aureus protease and thermolysin. Sequencing of the various peptides was achieved by a combination of manual dansyl-Edman degradation and automatic liquid-phase sequence analysis. The main characteristic of this cytochrome is that the haem-binding sequence Cys-Xaa-Yaa-Cys-His occurs in the C-terminal region of the polypeptide chain, the first cysteine being located 11 residues ahead of the C-terminal lysine-122. As such, the protein belongs to cytochrome c sequence class II (sensu Ambler). The cytochrome c-556 is the first example known of a class II cytochrome of the low-spin type isolated from an obligate aerobic organism.
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36
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Moore GR, McClune GJ, Clayden NJ, Williams RJ, Alsaadi BM, Angström J, Ambler RP, van Beeumen J, Tempst P, Bartsch RG, Meyer TE, Kamen MD. Metal coordination centres of class II cytochromes c. Eur J Biochem 1982; 123:73-80. [PMID: 6279397 DOI: 10.1111/j.1432-1033.1982.tb06500.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The class II cytochromes Rhodospirillum molischianum cytochrome c', Rhodopseudomonas palustris cytochrome C556 and Agrobacterium tumefaciens (B2a) cytochrome c556 have been investigated with a variety of spectroscopic techniques. The cytochrome c' was found to be high-spin and the two cytochromes c556 were found to be mainly low-spin and sx-coordinate with the fifth and sixth ligands being histidine and methionine. The implications of the different types of iron coordination are discussed.
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van Beeumen J, van der Branden C, Tempst P, de Ley J. A C-terminal haem-bound cytochrome c-556 from Agrobacterium tumefaciens, strain B-2a. Amino acid composition and N-terminal sequence analysis. FEBS Lett 1979; 101:336-8. [PMID: 221262 DOI: 10.1016/0014-5793(79)81038-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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