A depiction of the science indicated in the caption.

Fig. 1. HItln1 binding in a synthetic mixed microbial community. (A) Schematic of flow cytometry–based assay to measure soluble lectin binding to microbial isolates. Overlay of data from 0.1-μg hItln1/1 × 106 cells condition shown in (B) with the hItln1-positive binding region indicated. (B) Flow cytometry analysis of microbial isolates plotted as FSC against hItln1 binding (anti-Strep Oyster 645). Panels show 0.1-μg hItln1/1 × 106 cells condition. Staggered histograms of flow cytometry data plot cell count as a percent of the maximum against lectin binding (anti-Strep Oyster 645). Dot plots and histograms are color-coded according to the legend shown in (A). (C) Schematic of flow cytometry–based assay to measure soluble lectin binding to a synthetic mixture of microbial isolates. Flow cytometry analysis of synthetic mixed microbial community plotted as FSC against hItln1 binding (anti-Strep Oyster 645). Panels show 0-μg hItln1/1 × 106 cells and 0.1-μg hItln1/1 × 106 cells conditions. Histogram of flow cytometry data plots cell count as a percent of the maximum against lectin binding (anti-Strep Oyster 645) for the 0.1-μg hItln1/1 × 106 cells condition. Data are representative of two independent experiments.

Image courtesy of the researchers.

Kiessling paper published in Science Advances

by Department of Chemistry |
Categories: Faculty, Research

The paper, “Lectin-Seq: A method to profile lectin-microbe interactions in native communities", was published on July 28, 2023.

Members of Professor Laura Kiessling‘s lab have been studying the role of human lectins (carbohydrate-binding proteins), many of which are found at interfaces between our bodies and microbes (i.e., the gut, the lung, the blood). It is known that human lectins influence the microbiome, but how they influence it remains a mystery. The researchers have previously shown that the lectins bind microbial glycans. Those findings led to the interest in what microbes the lectins bind . In this collaborative study, published on July 28, 2023 and supported by the MIT Center for Microbiome Informatics and Therapeutics, the researchers developed a general strategy to relate glycan binding to microbe species identity.

Lectin-Seq: a method to profile lectin-microbe interactions in native communities
Robert L. McPherson, Christine R. Isabella, Rebecca L. Walker, Dallis Sergio, Sunhee Bae, Tony Gaca, Smrithi Raman, Le Thanh Tu Nguyen, Darryl A. Wesener, Melanie Halim, Michael G. Wuo, Amanda Dugan, Robert Kerby, Soumi Ghosh, Federico E. Rey, Catherine Dhennezel, Gleb Pishchany, Valerie Lensch, Hera Vlamakis, Eric J. Alm, Ramnik J. Xavier, and Laura L. Kiessling
Science Advances, July 28, 2023
DOI: 10.1126/sciadv.add8766

Abstract: Soluble human lectins are critical components of innate immunity. Genetic models suggest lectins influence host-resident microbiota, but their specificity for commensal and mutualist species is understudied. Elucidating lectins’ roles in regulating microbiota requires an understanding of which microbial species they bind within native communities. To profile human lectin recognition, members of the Kiessling Group developed Lectin-Seq. The researchers apply Lectin-Seq to human fecal microbiota using the soluble mannose-binding lectin (MBL) and intelectin-1 (hItln1). Although each lectin binds a substrantial percentage of the samples (10-20%), the microbial interactomes of MBL and hItln1 differ markedly in composition and diversity. MBL binding is highly selective for a small subset of species commonly associated with humans. In contrast, hItln1’s interaction profile encompasses a broad range of lower-abundance species. This data uncovers stark differences in the commensal recognition properties of human lectins.

Read the full text at Science Advances.

The Kiessling Group uses chemical biology to elucidate the biological roles of carbohydrates, with a focus on learning new mechanistic concepts.