algA (PA3551, P07874) notes

Identity

Swiss-Prot entry, 481 aa, "Alginate biosynthesis protein AlgA"; bifunctional
phosphomannose isomerase (PMI, EC 5.3.1.8) / GDP-mannose pyrophosphorylase
(GMP, EC 2.7.7.13), type II PMI family, NCBIfam TIGR01479, PANTHER
PTHR46390:SF1. algA is the 3'-terminal gene of the alginate biosynthetic
operon (algD ... algA).
Paralogues WbpW (PA5452, A-band LPS; reviewed in this batch) and PslB (Psl).

Literature

Shinabarger et al. 1991, PMID:1846611 (abstract only; JBC 1991, no PMC).
Purification of the bifunctional PMI-GMP from P. aeruginosa; PMI and GMP
co-purify through three chromatographic steps; kinetics for both reactions.
UniProt (Swiss-Prot) cites the same paper for N-terminal sequence (1-10),
catalytic activities, cofactor and kinetics, all ECO:0000269.
PMID:1846611
PMID:1846611
PMID:1846611

The alginic acid biosynthetic process IMP from this paper rests on the algA
point mutant; the abstract does not state the mutant's alginate phenotype,
but the role of AlgA in producing the GDP-mannose precursor of alginate is
well established and curated in Swiss-Prot. Accepted, as for algC.

Rocchetta et al. 1998, PMID:9781879 (wbpW paper) states that alginate
mannuronate and A-band rhamnose both derive from GDP-D-mannose, and that
wbpW algA double mutants still make some A-band (PslB compensates).

PseudoCAP IBA-seed assessment

Seeds from .cache/paint/IBD.gaf; E. coli ManC (P24174) GO:0004475 IDA
PMID:4908790 (EcoCyc) from QuickGO 2026-11-05.

PTN node node term n_seeds leaf IBAs seed annotation (term, evidence, PMID) verdict rationale other seeds IBD stands without this seed?
PTN000283179 GO:0004475 mannose-1-phosphate guanylyltransferase (GTP) activity 2 30 (26 taxa) GO:0004475, IDA, PMID:1846611 SOUND Purified enzyme with GMP forward and reverse kinetics; exactly the node term. Suits the PMI-GMP clade. E. coli ManC P24174 (IDA, PMID:4908790) Yes

The sister IBD at the same node, GO:0009298 GDP-mannose biosynthetic process,
is seeded by ManC and WbpW (see genes/PSEAE/wbpW, where the WbpW seed row has
a PSEUDOCAP evidence-code CHECK). Both node IBDs stand; no GO_CENTRAL defect
for PTN000283179. No PSEUDOCAP defect on algA.

Review decisions