2,3-Dihydroxypropane-1-sulfonate degraded by Cupriavidus pinatubonensis JMP134: purification of dihydroxypropanesulfonate 3-dehydrogenase

266

233

Dissolved organic matter (DOM) in the oceans is one of the largest pools of reduced carbon on Earth, comparable in size to the atmospheric CO 2 reservoir. A vast number of compounds are present in DOM, and they play important roles in all major element cycles, contribute to the storage of atmospheric CO 2 in the ocean, support marine ecosystems, and facilitate interactions between organisms. At the heart of the DOM cycle lie molecular-level relationships between the individual compounds in DOM and the members of the ocean microbiome that produce and consume them. In the past, these connections have eluded clear definition because of the sheer numerical complexity of both DOM molecules and microorganisms. Emerging tools in analytical chemistry, microbiology, and informatics are breaking down the barriers to a fuller appreciation of these connections. Here we highlight questions being addressed using recent methodological and technological developments in those fields and consider how these advances are transforming our understanding of some of the most important reactions of the marine carbon cycle.dissolved organic matter | marine microbes | cyberinfrastructure

Section: How Many Metabolic Pathways Are Required For the Bacterial Tmentioning

confidence: 99%

Section: How Many Metabolic Pathways Are Required For the Bacterial Tmentioning

confidence: 99%

Deciphering ocean carbon in a changing world

Moran

Kujawinski

Stubbins

et al. 2016

266

233

“…Later work demonstrated that SQ can be degraded completely by two-member bacterial communities, that is, by a primary degrader with transient release of SL or DHPS and a secondary degrader with release of sulfate (11,12). Pathways for the degradation of DHPS and SL, including desulfonation, have been described (13,15,29) where, briefly, DHPS is oxidized to SL and the SL is mineralized via one of three known pathways and desulfonative enzymes [i.e., SL sulfolyase (SuyAB; EC 4.4.1.24), sulfoacetaldehyde acetyltransferase (Xsc; EC 2.3.3.15), cysteate sulfolyase (CuyA; EC 4.4.1.25)]. However, details on the pathways, enzymes, and genes for the conversion of SQ to DHPS and SL were missing.…”

Section: Matching Mass Of the [M-h]mentioning

confidence: 99%

“…The SLA is reduced to 2,3-dihydroxypropane sulfonate (DHPS) by the SLA reductase, and the DHPS is excreted (12). Hence, E. coli K-12 can use only half of the carbon in SQ and is not able to catalyze a desulfonation reaction, whereas other bacteria can degrade DHPS [or the 3-sulfolactate (SL) formed from SQ, as discussed below] completely, including desulfonation and release of sulfate, via defined pathways (MetaCyc pathway PWY-6616) (13)(14)(15). Thus, the sulfur cycle for SQ can be closed within bacterial communities (11, 12 and cf.…”

mentioning

confidence: 99%

Entner–Doudoroff pathway for sulfoquinovose degradation in Pseudomonas putida SQ1

Felux

Spiteller

Klebensberger

et al. 2015

126

Sulfoquinovose (SQ; 6-deoxy-6-sulfoglucose) is the polar head group of the plant sulfolipid SQ-diacylglycerol, and SQ comprises a major proportion of the organosulfur in nature, where it is degraded by bacteria. A first degradation pathway for SQ has been demonstrated recently, a "sulfoglycolytic" pathway, in addition to the classical glycolytic (Embden-Meyerhof) pathway in Escherichia coli K-12; half of the carbon of SQ is abstracted as dihydroxyacetonephosphate (DHAP) and used for growth, whereas a C 3 -organosulfonate, 2,3-dihydroxypropane sulfonate (DHPS), is excreted. The environmental isolate Pseudomonas putida SQ1 is also able to use SQ for growth, and excretes a different C 3 -organosulfonate, 3-sulfolactate (SL). In this study, we revealed the catabolic pathway for SQ in P. putida SQ1 through differential proteomics and transcriptional analyses, by in vitro reconstitution of the complete pathway by five heterologously produced enzymes, and by identification of all four organosulfonate intermediates. The pathway follows a reaction sequence analogous to the Entner-Doudoroff pathway for glucose-6-phosphate: It involves an NAD + -dependent SQ dehydrogenase, 6-deoxy-6-sulfogluconolactone (SGL) lactonase, 6-deoxy-6-sulfogluconate (SG) dehydratase, and 2-keto-3,6-dideoxy-6-sulfogluconate (KDSG) aldolase. The aldolase reaction yields pyruvate, which supports growth of P. putida, and 3-sulfolactaldehyde (SLA), which is oxidized to SL by an NAD(P) + -dependent SLA dehydrogenase. All five enzymes are encoded in a single gene cluster that includes, for example, genes for transport and regulation. Homologous gene clusters were found in genomes of other P. putida strains, in other gamma-Proteobacteria, and in beta-and alpha-Proteobacteria, for example, in genomes of Enterobacteria, Vibrio, and Halomonas species, and in typical soil bacteria, such as Burkholderia, Herbaspirillum, and Rhizobium.bacterial biodegradation | organosulfonate | sulfolipid | 6-deoxy-6-sulfoglucose | sulfur cycle S ulfoquinovose (SQ; 6-deoxy-6-sulfoglucose) is the polar head group of the plant sulfolipids sulfoquinovosyl diacylglycerols (SQDGs), which were discovered more than 60 y ago (1). The sulfolipids are located in the photosynthetic (thylakoid) membranes of all higher plants, mosses, ferns, and algae, as well as in most photosynthetic bacteria. They are also present in some nonphotosynthetic bacteria, and SQ is in the surface layer of some archaea (2-4). SQ is continuously degraded in all environments where SQ is produced, or it would enrich in these environments. The complete degradation of SQ to, ultimately, CO 2 , concomitant with a recycling of the bound sulfur in the form of inorganic sulfate, is dominated by microbes (e.g., by soil bacteria) (2, 5-9). However, a more detailed exploration of SQ-degrading microbes, of their SQ-degradation pathways, and of the enzymes and genes involved has only recently been initiated (10-12). The common view on SQ degradation is based on the consideration that SQ is a structural analog of glucose-6...

“…S1). The enzymatic function of these bacterial genes was established previously (11,12), but their ecological role had remained unknown. Identification of both sulfonates as currencies in this model system suggests a diatom-derived oxidized organic sulfur pool that may be important in fueling the marine microbial food web.…”

Section: Significancementioning

confidence: 99%

Cryptic carbon and sulfur cycling between surface ocean plankton

Durham

Sharma

Luo

et al. 2014

338

342

About half the carbon fixed by phytoplankton in the ocean is taken up and metabolized by marine bacteria, a transfer that is mediated through the seawater dissolved organic carbon (DOC) pool. The chemical complexity of marine DOC, along with a poor understanding of which compounds form the basis of trophic interactions between bacteria and phytoplankton, have impeded efforts to identify key currencies of this carbon cycle link. Here, we used transcriptional patterns in a bacterial-diatom model system based on vitamin B 12 auxotrophy as a sensitive assay for metabolite exchange between marine plankton. The most highly up-regulated genes (up to 374-fold) by a marine Roseobacter clade bacterium when cocultured with the diatom Thalassiosira pseudonana were those encoding the transport and catabolism of 2,3-dihydroxypropane-1-sulfonate (DHPS). This compound has no currently recognized role in the marine microbial food web. As the genes for DHPS catabolism have limited distribution among bacterial taxa, T. pseudonana may use this sulfonate for targeted feeding of beneficial associates. Indeed, DHPS was both a major component of the T. pseudonana cytosol and an abundant microbial metabolite in a diatom bloom in the eastern North Pacific Ocean. Moreover, transcript analysis of the North Pacific samples provided evidence of DHPS catabolism by Roseobacter populations. Other such biogeochemically important metabolites may be common in the ocean but difficult to discriminate against the complex chemical background of seawater. Bacterial transformation of this diatom-derived sulfonate represents a previously unidentified and likely sizeable link in both the marine carbon and sulfur cycles.