New mechanisms for bacterial degradation of sulfoquinovose

Abstract

Sulfoquinovose (SQ, 6-deoxy-6-sulfo-D-glucose) is a sulfo-sugar with a ubiquitous distribution in the environment due to its production by plants and other photosynthetic organisms. Bacteria play an important role in degradation of SQ, and recycling of its constituent sulfur and carbon. Since its discovery in 1963, SQ was noted to have a structural resemblance to glucose-6-phosphate, and proposed to be degraded through a pathway analogous to glycolysis, termed sulfoglycolysis. Studies in recent years have uncovered an unexpectedly diverse array of sulfoglycolytic pathways in different bacteria, including one analogous to the Embden-Meyerhof-Parnas pathway (sulfo-EMP), one analogous to the Entner-Doudoroff pathway (sulfo-ED), and two involving sulfo-sugar cleavage by a transaldolase (sulfo-TAL) and transketolase (sulfo-TK) respectively, analogous to reactions in the pentose phosphate (PP) pathway. In addition, a non-sulfoglycolytic SQ degradation pathway was also reported, involving oxygenolytic C-S cleavage catalyzed by a homolog of alkanesulfonate monooxygenase (sulfo-ASMO). Here we review the discovery of these new mechanisms of SQ degradation, and lessons learnt in the study of new catabolic enzymes and pathways in bacteria.

Protocatechuic acid induces endogenous oxidative stress in CR-hvKP by regulating the EMP-PPP pathway

“…Due to the antibacterial activity of certain secondary metabolites, such as pyocyanin (PYO) in Pseudomonas aeruginosa and pyocyanin in Staphylococcus aureus [77], we can also develop antibacterial drug adjuvants targeting the metabolites themselves. Since there is a bidirectional influence between bacterial cell membrane and bacterial metabolic activity [42][45], the function of biofilms is also regulated by bacterial metabolism [78–79]. Therefore, to gain a deeper understanding of the biological mechanism of PCA on CR-hvKP, metabolomics methods were used to describe the major changes in the biological processes of CR-hvKP after PCA treatment.…”

HMSS2: An advanced tool for the analysis of sulphur metabolism, including organosulphur compound transformation, in genome and metagenome assemblies

“…Mainly produced by plants, algae and cyanobacteria, its turnover rate has been estimated at around 10 billion tonnes per year (Goddard‐Borger & Williams, 2017). The bacterial decomposition of sulphoquinovose involves several different pathways similar to the degradation of glucose (Figure 2a), with the exception that smaller sulphonated compounds are often released, since complete utilization with release of free sulphur by a single organism is often not possible (Wei et al, 2022). Release and scavenging of sulphonated intermediates is achieved by various transport systems (Figure 2b).…”

Widespread Family of NAD+-Dependent Sulfoquinovosidases at the Gateway to Sulfoquinovose Catabolism

“…The mineralization of SQ occurs through various sulfoglycolytic and sulfolytic pathways that enable utilization of its carbon and sulfur content (Figures a and S1, S2). − Sulfoglycolytic pathways break the sugar chain to release C2 or C3 organosulfonates, which are substrates for secondary biomineralization pathways that catabolise these short-chain organosulfonates and release inorganic sulfite. Sulfolytic pathways cleave the C–S bond to release sulfite and provide glucose to fuel glycolysis.…”