Gene Ontology annotation through association of InterPro records with GO terms

The InterPro peptidase U4 (SpoIIGA/sporulation-specific aspartic protease) family record is mapped to asexual sporulation and related process terms.

Gene Ontology annotation based on UniProtKB/Swiss-Prot keyword mapping

UniProt keywords Hydrolase, Protease, Aspartyl protease, and Sporulation for SpoIIGA map to peptidase activity, hydrolase activity, and sporulation GO terms.

Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping, accompanied by conservative changes to GO terms applied by UniProt

The UniProt cell-membrane subcellular location for SpoIIGA (a multi-pass membrane protein anchored at the sporulation septum) is mapped to plasma membrane (GO:0005886).

GO_REF:0000120

Combined Automated Annotation using Multiple IEA Methods

Consensus IEA pipelines assign aspartic-type endopeptidase activity and general proteolysis to SpoIIGA, consistent with the manually curated function.

PMID:18378688

Evidence that the Bacillus subtilis SpoIIGA protein is a novel type of signal-transducing aspartic protease.

SpoIIGA is a membrane-associated aspartic protease

"Modeling and mutational analyses provide evidence that SpoIIGA is a novel type of aspartic protease whose C-terminal half forms a dimer similar to the human immunodeficiency virus type 1 protease."
SpoIIGA C-terminal domain forms a dimer similar to HIV-1 protease

"SpoIIGA is a novel type of aspartic protease whose C-terminal half forms a dimer similar to the human immunodeficiency virus type 1 protease."
SpoIIR and SpoIIGA are necessary and sufficient for pro-sigmaE processing

"We report that expression of SpoIIR, a putative signaling protein normally made in the forespore, and SpoIIGA, a putative protease, is necessary and sufficient for accurate, rapid, and abundant processing of pro-sigma(E) to sigma(E) in Escherichia coli."
SpoIIGA interacts with SpoIIR signaling protein

"Also, SpoIIGA interacts with SpoIIR."
SpoIIGA self-associates when membrane-associated

"We found that SpoIIGA expressed in E. coli is membrane-associated and that after detergent treatment SpoIIGA was self-associated."
Catalytic aspartate D183 is essential for activity

"Modeling and mutational analyses provide evidence that SpoIIGA is a novel type of aspartic protease whose C-terminal half forms a dimer similar to the human immunodeficiency virus type 1 protease."

PMID:21362630

Substrate specificity of SpoIIGA, a signal-transducing aspartic protease in Bacilli.

Residues D24 and E25 of pro-sigmaE are critical for cleavage

"By co-expressing proteins in Escherichia coli, it was shown that charge reversal substitutions for acidic residues 24 and 25 of Pro-σ(E), and for basic residues 245 and 284 of SpoIIGA, impaired cleavage."
Residues R245 and K284 of SpoIIGA are important for substrate recognition

"By co-expressing proteins in Escherichia coli, it was shown that charge reversal substitutions for acidic residues 24 and 25 of Pro-σ(E), and for basic residues 245 and 284 of SpoIIGA, impaired cleavage."
B. subtilis SpoIIGA can cleave pro-sigmaE from B. licheniformis and B. halodurans

"Bacillus subtilis SpoIIGA cleaved Pro-σ(E) orthologs from Bacillus licheniformis and Bacillus halodurans, but not from Bacillus cereus."
B. cereus pro-sigmaE is not cleaved unless distal pro-sequence is modified

"A triple substitution in the pro-sequence of B. cereus Pro-σ(E) allowed cleavage by B. subtilis SpoIIGA, indicating that residues distal from the cleavage site contribute to substrate specificity."
Cross-species differences in substrate specificity exist among Bacillus SpoIIGA orthologs

"Co-expression of SpoIIGA and Pro-σ(E) orthologs in different combinations suggested that B. licheniformis SpoIIGA has a relatively narrow substrate specificity as compared with B. subtilis SpoIIGA, whereas B. cereus SpoIIGA and B. halodurans SpoIIGA appear to have broader substrate specificity."

file:BACSU/spoIIGA/spoIIGA-deep-research-falcon.md

Deep research review of SpoIIGA function

SpoIIGA is the dedicated processing protease that converts pro-sigmaE to active sigmaE

"SpoIIGA is the dedicated processing protease that converts pro-σE (Pro-σE) to active σE in the mother cell, initiating the σE transcriptional program required for early mother-cell development during sporulation."