Production of α-Galactosylceramide by a Prominent Member of the Human Gut Microbiota

Laura C. Wieland Brown, Cristina Penaranda, Purna C Kashyap, Brianna B. Williams, Jon Clardy, Mitchell Kronenberg, Justin L. Sonnenburg, Laurie E. Comstock, Jeffrey A. Bluestone, Michael A. Fischbach

Research output: Contribution to journalArticle

116 Citations (Scopus)

Abstract

While the human gut microbiota are suspected to produce diffusible small molecules that modulate host signaling pathways, few of these molecules have been identified. Species of Bacteroides and their relatives, which often comprise >50% of the gut community, are unusual among bacteria in that their membrane is rich in sphingolipids, a class of signaling molecules that play a key role in inducing apoptosis and modulating the host immune response. Although known for more than three decades, the full repertoire of Bacteroides sphingolipids has not been defined. Here, we use a combination of genetics and chemistry to identify the sphingolipids produced by Bacteroides fragilis NCTC 9343. We constructed a deletion mutant of BF2461, a putative serine palmitoyltransferase whose yeast homolog catalyzes the committed step in sphingolipid biosynthesis. We show that the Δ2461 mutant is sphingolipid deficient, enabling us to purify and solve the structures of three alkaline-stable lipids present in the wild-type strain but absent from the mutant. The first compound was the known sphingolipid ceramide phosphorylethanolamine, and the second was its corresponding dihydroceramide base. Unexpectedly, the third compound was the glycosphingolipid α-galactosylceramide (α-GalCerBf), which is structurally related to a sponge-derived sphingolipid (α-GalCer, KRN7000) that is the prototypical agonist of CD1d-restricted natural killer T (iNKT) cells. We demonstrate that α-GalCerBf has similar immunological properties to KRN7000: it binds to CD1d and activates both mouse and human iNKT cells both in vitro and in vivo. Thus, our study reveals BF2461 as the first known member of the Bacteroides sphingolipid pathway, and it indicates that the committed steps of the Bacteroides and eukaryotic sphingolipid pathways are identical. Moreover, our data suggest that some Bacteroides sphingolipids might influence host immune homeostasis.

Original languageEnglish (US)
Article numbere1001610
JournalPLoS Biology
Volume11
Issue number7
DOIs
StatePublished - Jul 2013
Externally publishedYes

Fingerprint

Galactosylceramides
sphingolipids
Sphingolipids
intestinal microorganisms
Bacteroides
Natural Killer T-Cells
mutants
Molecules
serine C-palmitoyltransferase
Serine C-Palmitoyltransferase
Bacteroides fragilis
Gastrointestinal Microbiome
glycosphingolipids
Glycosphingolipids
ceramides
Ceramides
Biosynthesis
natural killer cells
Porifera
Yeast

ASJC Scopus subject areas

  • Agricultural and Biological Sciences(all)
  • Biochemistry, Genetics and Molecular Biology(all)
  • Immunology and Microbiology(all)
  • Neuroscience(all)

Cite this

Wieland Brown, L. C., Penaranda, C., Kashyap, P. C., Williams, B. B., Clardy, J., Kronenberg, M., ... Fischbach, M. A. (2013). Production of α-Galactosylceramide by a Prominent Member of the Human Gut Microbiota. PLoS Biology, 11(7), [e1001610]. https://doi.org/10.1371/journal.pbio.1001610

Production of α-Galactosylceramide by a Prominent Member of the Human Gut Microbiota. / Wieland Brown, Laura C.; Penaranda, Cristina; Kashyap, Purna C; Williams, Brianna B.; Clardy, Jon; Kronenberg, Mitchell; Sonnenburg, Justin L.; Comstock, Laurie E.; Bluestone, Jeffrey A.; Fischbach, Michael A.

In: PLoS Biology, Vol. 11, No. 7, e1001610, 07.2013.

Research output: Contribution to journalArticle

Wieland Brown, LC, Penaranda, C, Kashyap, PC, Williams, BB, Clardy, J, Kronenberg, M, Sonnenburg, JL, Comstock, LE, Bluestone, JA & Fischbach, MA 2013, 'Production of α-Galactosylceramide by a Prominent Member of the Human Gut Microbiota', PLoS Biology, vol. 11, no. 7, e1001610. https://doi.org/10.1371/journal.pbio.1001610
Wieland Brown LC, Penaranda C, Kashyap PC, Williams BB, Clardy J, Kronenberg M et al. Production of α-Galactosylceramide by a Prominent Member of the Human Gut Microbiota. PLoS Biology. 2013 Jul;11(7). e1001610. https://doi.org/10.1371/journal.pbio.1001610
Wieland Brown, Laura C. ; Penaranda, Cristina ; Kashyap, Purna C ; Williams, Brianna B. ; Clardy, Jon ; Kronenberg, Mitchell ; Sonnenburg, Justin L. ; Comstock, Laurie E. ; Bluestone, Jeffrey A. ; Fischbach, Michael A. / Production of α-Galactosylceramide by a Prominent Member of the Human Gut Microbiota. In: PLoS Biology. 2013 ; Vol. 11, No. 7.
@article{2a03ce35004c48259e18d8f4093fff0d,
title = "Production of α-Galactosylceramide by a Prominent Member of the Human Gut Microbiota",
abstract = "While the human gut microbiota are suspected to produce diffusible small molecules that modulate host signaling pathways, few of these molecules have been identified. Species of Bacteroides and their relatives, which often comprise >50{\%} of the gut community, are unusual among bacteria in that their membrane is rich in sphingolipids, a class of signaling molecules that play a key role in inducing apoptosis and modulating the host immune response. Although known for more than three decades, the full repertoire of Bacteroides sphingolipids has not been defined. Here, we use a combination of genetics and chemistry to identify the sphingolipids produced by Bacteroides fragilis NCTC 9343. We constructed a deletion mutant of BF2461, a putative serine palmitoyltransferase whose yeast homolog catalyzes the committed step in sphingolipid biosynthesis. We show that the Δ2461 mutant is sphingolipid deficient, enabling us to purify and solve the structures of three alkaline-stable lipids present in the wild-type strain but absent from the mutant. The first compound was the known sphingolipid ceramide phosphorylethanolamine, and the second was its corresponding dihydroceramide base. Unexpectedly, the third compound was the glycosphingolipid α-galactosylceramide (α-GalCerBf), which is structurally related to a sponge-derived sphingolipid (α-GalCer, KRN7000) that is the prototypical agonist of CD1d-restricted natural killer T (iNKT) cells. We demonstrate that α-GalCerBf has similar immunological properties to KRN7000: it binds to CD1d and activates both mouse and human iNKT cells both in vitro and in vivo. Thus, our study reveals BF2461 as the first known member of the Bacteroides sphingolipid pathway, and it indicates that the committed steps of the Bacteroides and eukaryotic sphingolipid pathways are identical. Moreover, our data suggest that some Bacteroides sphingolipids might influence host immune homeostasis.",
author = "{Wieland Brown}, {Laura C.} and Cristina Penaranda and Kashyap, {Purna C} and Williams, {Brianna B.} and Jon Clardy and Mitchell Kronenberg and Sonnenburg, {Justin L.} and Comstock, {Laurie E.} and Bluestone, {Jeffrey A.} and Fischbach, {Michael A.}",
year = "2013",
month = "7",
doi = "10.1371/journal.pbio.1001610",
language = "English (US)",
volume = "11",
journal = "PLoS Biology",
issn = "1544-9173",
publisher = "Public Library of Science",
number = "7",

}

TY - JOUR

T1 - Production of α-Galactosylceramide by a Prominent Member of the Human Gut Microbiota

AU - Wieland Brown, Laura C.

AU - Penaranda, Cristina

AU - Kashyap, Purna C

AU - Williams, Brianna B.

AU - Clardy, Jon

AU - Kronenberg, Mitchell

AU - Sonnenburg, Justin L.

AU - Comstock, Laurie E.

AU - Bluestone, Jeffrey A.

AU - Fischbach, Michael A.

PY - 2013/7

Y1 - 2013/7

N2 - While the human gut microbiota are suspected to produce diffusible small molecules that modulate host signaling pathways, few of these molecules have been identified. Species of Bacteroides and their relatives, which often comprise >50% of the gut community, are unusual among bacteria in that their membrane is rich in sphingolipids, a class of signaling molecules that play a key role in inducing apoptosis and modulating the host immune response. Although known for more than three decades, the full repertoire of Bacteroides sphingolipids has not been defined. Here, we use a combination of genetics and chemistry to identify the sphingolipids produced by Bacteroides fragilis NCTC 9343. We constructed a deletion mutant of BF2461, a putative serine palmitoyltransferase whose yeast homolog catalyzes the committed step in sphingolipid biosynthesis. We show that the Δ2461 mutant is sphingolipid deficient, enabling us to purify and solve the structures of three alkaline-stable lipids present in the wild-type strain but absent from the mutant. The first compound was the known sphingolipid ceramide phosphorylethanolamine, and the second was its corresponding dihydroceramide base. Unexpectedly, the third compound was the glycosphingolipid α-galactosylceramide (α-GalCerBf), which is structurally related to a sponge-derived sphingolipid (α-GalCer, KRN7000) that is the prototypical agonist of CD1d-restricted natural killer T (iNKT) cells. We demonstrate that α-GalCerBf has similar immunological properties to KRN7000: it binds to CD1d and activates both mouse and human iNKT cells both in vitro and in vivo. Thus, our study reveals BF2461 as the first known member of the Bacteroides sphingolipid pathway, and it indicates that the committed steps of the Bacteroides and eukaryotic sphingolipid pathways are identical. Moreover, our data suggest that some Bacteroides sphingolipids might influence host immune homeostasis.

AB - While the human gut microbiota are suspected to produce diffusible small molecules that modulate host signaling pathways, few of these molecules have been identified. Species of Bacteroides and their relatives, which often comprise >50% of the gut community, are unusual among bacteria in that their membrane is rich in sphingolipids, a class of signaling molecules that play a key role in inducing apoptosis and modulating the host immune response. Although known for more than three decades, the full repertoire of Bacteroides sphingolipids has not been defined. Here, we use a combination of genetics and chemistry to identify the sphingolipids produced by Bacteroides fragilis NCTC 9343. We constructed a deletion mutant of BF2461, a putative serine palmitoyltransferase whose yeast homolog catalyzes the committed step in sphingolipid biosynthesis. We show that the Δ2461 mutant is sphingolipid deficient, enabling us to purify and solve the structures of three alkaline-stable lipids present in the wild-type strain but absent from the mutant. The first compound was the known sphingolipid ceramide phosphorylethanolamine, and the second was its corresponding dihydroceramide base. Unexpectedly, the third compound was the glycosphingolipid α-galactosylceramide (α-GalCerBf), which is structurally related to a sponge-derived sphingolipid (α-GalCer, KRN7000) that is the prototypical agonist of CD1d-restricted natural killer T (iNKT) cells. We demonstrate that α-GalCerBf has similar immunological properties to KRN7000: it binds to CD1d and activates both mouse and human iNKT cells both in vitro and in vivo. Thus, our study reveals BF2461 as the first known member of the Bacteroides sphingolipid pathway, and it indicates that the committed steps of the Bacteroides and eukaryotic sphingolipid pathways are identical. Moreover, our data suggest that some Bacteroides sphingolipids might influence host immune homeostasis.

UR - http://www.scopus.com/inward/record.url?scp=84880941717&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84880941717&partnerID=8YFLogxK

U2 - 10.1371/journal.pbio.1001610

DO - 10.1371/journal.pbio.1001610

M3 - Article

C2 - 23874157

AN - SCOPUS:84880941717

VL - 11

JO - PLoS Biology

JF - PLoS Biology

SN - 1544-9173

IS - 7

M1 - e1001610

ER -