Expression, purification, and characterization of NosL, a novel Cu(I) protein of the nitrous oxide reductase (nos) gene cluster

Recently, we reported the purification and characterization of three distinct lantibiotics (named suicin 90-1330, suicin 3908, and suicin 65) produced by Streptococcus suis. In this study, we investigated the distribution of the three suicin lantibiotic gene clusters among serotype 2 S. suis strains belonging to sequence type (ST) 25 and ST28, the two dominant STs identified in North America. The genomes of 102 strains were interrogated for the presence of suicin gene clusters encoding suicins 90-1330, 3908, and 65. The gene cluster encoding suicin 65 was the most prevalent and mainly found among ST25 strains. In contrast, none of the genes related to suicin 90-1330 production were identified in 51 ST25 strains nor in 35/51 ST28 strains. However, the complete suicin 90-1330 gene cluster was found in ten ST28 strains, although some genes in the cluster were truncated in three of these isolates. The vast majority (101/102) of S. suis strains did not possess any of the genes encoding suicin 3908. In conclusion, this study indicates heterogeneous distribution of suicin genes in S. suis.

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Characterization of the Copper−Sulfur Chromophores in Nitrous Oxide Reductase by Resonance Raman Spectroscopy: Evidence for Sulfur Coordination in the Catalytic Cluster

Journal of the American Chemical Society ◽

10.1021/ja994322i ◽

2001 ◽

Vol 123 (4) ◽

pp. 576-587 ◽

Cited By ~ 41

Author(s):

Marcela L. Alvarez ◽

Jingyuan Ai ◽

Walter Zumft ◽

Joann Sanders-Loehr ◽

David M. Dooley

Keyword(s):

Raman Spectroscopy ◽

Nitrous Oxide ◽

Resonance Raman Spectroscopy ◽

Resonance Raman ◽

Nitrous Oxide Reductase

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Gene Cluster on pAO1 of Arthrobacter nicotinovorans Involved in Degradation of the Plant Alkaloid Nicotine: Cloning, Purification, and Characterization of 2,6-Dihydroxypyridine 3-Hydroxylase

Journal of Bacteriology ◽

10.1128/jb.183.18.5262-5267.2001 ◽

2001 ◽

Vol 183 (18) ◽

pp. 5262-5267 ◽

Cited By ~ 62

Author(s):

Daniel Baitsch ◽

Cristinel Sandu ◽

Roderich Brandsch ◽

Gabor L. Igloi

Keyword(s):

Gene Cluster ◽

Flavin Adenine Dinucleotide ◽

Open Reading Frames ◽

Hypothetical Proteins ◽

Purification And Characterization ◽

Irreversible Inhibitors ◽

Nicotine Degradation ◽

Arthrobacter Nicotinovorans ◽

Reading Frames

ABSTRACT A 27,690-bp gene cluster involved in the degradation of the plant alkaloid nicotine was characterized from the plasmid pAO1 ofArthrobacter nicotinovorans. The genes of the heterotrimeric, molybdopterin cofactor (MoCo)-, flavin adenine dinucleotide (FAD)-, and [Fe-S] cluster-dependent 6-hydroxypseudooxynicotine (ketone) dehydrogenase (KDH) were identified within this cluster. The gene of the large MoCo subunit of KDH was located 4,266 bp from the FAD and [Fe-S] cluster subunit genes. Deduced functions of proteins encoded by open reading frames (ORFs) of the cluster were correlated to individual steps in nicotine degradation. The gene for 2,6-dihydroxypyridine 3-hydroxylase was cloned and expressed in Escherichia coli. The purified homodimeric enzyme of 90 kDa contained 2 mol of tightly bound FAD per mol of dimer. Enzyme activity was strictly NADH-dependent and specific for 2,6-dihydroxypyridine. 2,3-Dihydroxypyridine and 2,6-dimethoxypyridine acted as irreversible inhibitors. Additional ORFs were shown to encode hypothetical proteins presumably required for holoenzyme assembly, interaction with the cell membrane, and transcriptional regulation, including a MobA homologue predicted to be specific for the synthesis of the molybdopterin cytidine dinucleotide cofactor.

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