biostudies-literatureUnknown14(1)Nagano TAn insect-associated bacterium, <i>Streptomyces</i> sp. SirexAA-E (SirexAA-E) secretes plant biomass-degrading enzymes depending on the available cell wall materials. SirexAA-E readily utilizes xylan, one of the major hemicelluloses. However, the enzyme composition and pathways supporting xylan metabolism in SirexAA-E and other Streptomycetes have not been reported. We aimed to understand changes in both extracellular and intracellular protein productions by cultivating SirexAA-E in defined media containing either xylose, xylobiose, or xylan. Proteomics showed each carbon source gave specific extracellular protein composition when compared to glucose. Furthermore, intracellular proteomics using a pair-wise Tandem Mass Tag (TMT)-labeling LC-MS/MS identified 1,037 proteins with changes in thMicrobiology spectrume0225125https://www.ebi.ac.uk/biostudies/studies/S-EPMC12772271biostudies-literatureMulti-proteomics reveals integrated metabolic and regulatory networks for xylan catabolism in &lt;i&gt;Streptomyces&lt;/i&gt; sp. SirexAA-E.PMC12772271Fox BGBanko PKumar VNagano TOhashi KTakasuka TEHori CfalseMulti-proteomics reveals integrated metabolic and regulatory networks for xylan catabolism in &lt;i&gt;Streptomyces&lt;/i&gt; sp. SirexAA-E.An insect-associated bacterium, <i>Streptomyces</i> sp. SirexAA-E (SirexAA-E) secretes plant biomass-degrading enzymes depending on the available cell wall materials. SirexAA-E readily utilizes xylan, one of the major hemicelluloses. However, the enzyme composition and pathways supporting xylan metabolism in SirexAA-E and other Streptomycetes have not been reported. We aimed to understand changes in both extracellular and intracellular protein productions by cultivating SirexAA-E in defined media containing either xylose, xylobiose, or xylan. Proteomics showed each carbon source gave specific extracellular protein composition when compared to glucose. Furthermore, intracellular proteomics using a pair-wise Tandem Mass Tag (TMT)-labeling LC-MS/MS identified 1,037 proteins with changes in th2026-01-01T00:00:00Z2026 Jan2026-06-06T10:53:03.757Z2026-05-29T03:11:57.637ZS-EPMC127722714126426010.1128/spectrum.02251-25