glgA

Summary: Strong ortholog and pathway-architecture evidence supports UDP-glucose specificity.

Reason: Purified P. aeruginosa PAO1 GlgA preferentially uses UDP-glucose, and the paper explicitly relates this specificity to the absence of glgC across Pseudomonas spp. Q88FN9 and the assayed PAO1 enzyme share PTHR45825:SF8, and KT2440 likewise lacks canonical GlgC. This supports transfer of the UDP-specific function while retaining direct Q88FN9 kinetics as a knowledge gap.

Summary: GlgA supplies the integrated Pseudomonas pathway that produces branched storage alpha-glucan.

Reason: The reviewed HAMAP assignment places Q88FN9 in glycogen biosynthesis, and experimental analysis of the close P. aeruginosa pathway shows GlgA-dependent formation of linear alpha-1,4-glucan. PAO1 GlgB can branch that product when overexpressed in a sensitized background, but physiological flux normally runs rapidly through TreY/TreZ toward trehalose or maltose and then through GlgE/GlgB to branched polymer. The biological-process annotation captures participation in that integrated biosynthetic pathway; it does not require a dominant direct GlgA-to-GlgB route.

Summary: The HAMAP-derived ADP-glucose assignment conflicts with Pseudomonas ortholog and pathway evidence.

Reason: UniProt/HAMAP assigns EC 2.4.1.21/RHEA:18189 and ADP-glucose to Q88FN9. In contrast, purified P. aeruginosa PAO1 GlgA preferentially polymerizes UDP-glucose, and the study links this result to the absence of glgC in Pseudomonas spp. The matching glgC-negative KT2440 pathway architecture makes the ADP-glucose-specific electronic annotation unsupported. The same-subfamily PAO1 ortholog is UDP-preferring, and KT2440 lacks the GlgC source of ADP-glucose; GO:0009011 therefore represents the wrong donor- specific sibling activity for this Pseudomonas enzyme.

Summary: Correct but less informative than the supported UDP-glucose-specific activity.

Reason: GlgA is securely a glycosyltransferase, but GO:0004373 captures both alpha-1,4-glucan chain extension and the supported UDP-glucose donor.

Proposed replacements: alpha-1,4-glucan glucosyltransferase (UDP-glucose donor) activity

Summary: GlgA-dependent linear glucan formation supports the broader alpha-glucan biosynthetic process.

Reason: Purified PAO1 GlgA forms linear alpha-glucan, and Q88FN9 is the close KT2440 family member in the conserved Pseudomonas alpha-glucan locus. This term records formation of the immediate linear alpha-glucan product alongside participation in integrated glycogen biosynthesis.