"Total exopolysaccharide (EPS) and alginate production increased with increasing matric, but not solute, stress severity, and alginate was a significant component, but not the major component, of EPS."

"Alginate influenced biofilm architecture, resulting in biofilms that were taller, covered less surface area, and had a thicker EPS layer at the air interface than those formed by an mt-2 algD mutant under water-limiting conditions, properties that could contribute to less evaporative water loss."

"Alginate deficiency decreased survival of desiccation not only by P. putida but also by Pseudomonas aeruginosa PAO1 and Pseudomonas syringae pv. syringae B728a."

"Under water-limiting conditions, ROS accumulation is greater in an DeltaalgD mutant compared with the wild type, suggesting that the exopolysaccharide alginate attenuates the extent of dehydration-mediated oxidative stress."

"Here we report that during growth under water-limiting conditions and when biofilms become dehydrated most residents transiently express the alginate biosynthesis genes leading to distinct spatial patterns as the biofilm ages."

"Under water-limiting conditions Pseudomonas putida produces the exopolysaccharide alginate, which influences biofilm development and facilitates maintaining a hydrated microenvironment."

"The gene clusters alg and bcs, which code for proteins mediating alginate and cellulose biosynthesis, were found to play minor roles in P. putida KT2440 biofilm formation and stability under the conditions tested."

"Upregulation of alginate genes was notable in this early response."

"PP_1288 is explicitly annotated as algD (GDP-mannose 6-dehydrogenase)"

"AlgD (GDP-mannose 6-dehydrogenase; GMD) is a cytosolic enzyme in the **UDP-glucose/GDP-mannose dehydrogenase family** that catalyzes the **precursor-forming step** for bacterial alginate biosynthesis."

"AlgD catalyzes the **irreversible oxidation of GDP-mannose to GDP-mannuronate (GDP-mannuronic acid; GDP-ManA)**, supplying the activated uronic-acid building block used for polymer formation."

"The reaction is **NAD+-dependent**, and activity is commonly monitored by **NADH formation** (A340)."

"algD/PP_1288 is reported as significantly induced under water-limited conditions, with a reported **log2 fold-change of 3.26** in wild type at **0.4 MPa** matric potential"

"multiple authoritative descriptions of the pathway place AlgD function in the **cytoplasmic precursor synthesis stage** (GDP-mannuronate generation), upstream of membrane/periplasmic polymerization and export. This strongly supports a **cytosolic localization/function** for AlgD in KT2440 by pathway conservation."

"The enzyme is described as having an **N-terminal domain** that binds **NAD+ and GDP-mannose**, and a **C-terminal domain** containing an essential catalytic **cysteine** (reported as Cys268 in that article)."