Harry J. Gilbert

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Harry Gilbert

Professor Harry Gilbert FMedSci FRS (cropped).jpg
Gilbert in 2016
Alma mater
Employer
Scientific career
Fields
Thesis Studies on native and mutant forms of IMP dehydrogenase in Escherichia coli K12  (1979)
Website ncl.ac.uk/camb/staff/profile/harrygilbert.html

Harry J. Gilbert FRS FMedSci [2] (born 1953) is Professor of Agricultural Biochemistry and Nutrition in the Institute For Cell and Molecular Biosciences at Newcastle University. [1] [3]

Contents

Education

Gilbert was educated at the University of Southampton graduating with a Bachelor of Science degree in 1975 [3] followed by a PhD for research investigating mutant forms of the enzyme IMP dehydrogenase in Escherichia coli K12 in 1978. [4]

Research

Since taking up a lectureship at Newcastle University in 1985 Gilbert's research has focussed on enzymes, primarily glycoside hydrolases, which attack complex carbohydrates. These enzymes are of considerable biological and industrial importance. Gilbert has used structure-function studies to dissect the contribution of non-catalytic carbohydrate binding modules (CBMs) [5] in targeting enzymes to complex insoluble structures exemplified by the plant cell wall, thereby overcoming the access problem. [6] [7]

He has extended his studies on carbohydrate binding modules to explore how glycoside hydrolases are able to select specific substrates and modes of action. Using structure-based strategies, he has exploited this fundamental understanding of enzyme specificity to engineer novel catalytic functions into these biological catalysts.

As of 2016, Gilbert has been dissecting the mechanisms of glycans utilisation by gut bacteria, in the human microbiota. [8] His work has led to the presentation of a selfish model for the metabolism of highly complex carbohydrates by members of this ecosystem. [9] [10] His work has implications on resource allocation within the human microbiota, which could impact on dietary strategies that maximise the impact of this microbial ecology on health.

From 2008 to 2010 he was appointed an Eminent Scholar in Bioenergy at the University of Georgia, in the USA. [11] Gilbert's research has been funded by the Agricultural and Food Research Council (AFRC), the Biotechnology and Biological Sciences Research Council (BBSRC), the National Science Foundation (NSF), the United States Department of Energy (DOE), the National Institutes of Health (NIH), the Wellcome Trust and the European Research Council (ERC). [11]

Awards and honours

Gilbert was elected a Fellow of the Royal Society (FRS) in 2016 [2] and a Fellow of the Academy of Medical Sciences.[ when? ]

Related Research Articles

<span class="mw-page-title-main">Cellulase</span> Class of enzymes

Cellulase is any of several enzymes produced chiefly by fungi, bacteria, and protozoans that catalyze cellulolysis, the decomposition of cellulose and of some related polysaccharides:

<span class="mw-page-title-main">Acarbose</span> Chemical compound

Acarbose (INN) is an anti-diabetic drug used to treat diabetes mellitus type 2 and, in some countries, prediabetes. It is a generic sold in Europe and China as Glucobay, in North America as Precose, and in Canada as Prandase. It is cheap and popular in China, but not in the U.S. One physician explains that use in the U.S. is limited because it is not potent enough to justify the side effects of diarrhea and flatulence. However, a large study concluded in 2013 that "acarbose is effective, safe and well tolerated in a large cohort of Asian patients with type 2 diabetes." A possible explanation for the differing opinions is an observation that acarbose is significantly more effective in patients eating a relatively high carbohydrate Eastern diet.

<span class="mw-page-title-main">Natural gum</span> Thickening agent

Natural gums are polysaccharides of natural origin, capable of causing a large increase in a solution's viscosity, even at small concentrations. They are mostly botanical gums, found in the woody elements of plants or in seed coatings.

<span class="mw-page-title-main">Gut microbiota</span> Community of microorganisms in the gut

Gut microbiota, gut microbiome, or gut flora, are the microorganisms, including bacteria, archaea, fungi, and viruses, that live in the digestive tracts of animals. The gastrointestinal metagenome is the aggregate of all the genomes of the gut microbiota. The gut is the main location of the human microbiome. The gut microbiota has broad impacts, including effects on colonization, resistance to pathogens, maintaining the intestinal epithelium, metabolizing dietary and pharmaceutical compounds, controlling immune function, and even behavior through the gut–brain axis.

Cellulosomes are multi-enzyme extracellular complexes. Cellulosomes are associated with the cell surface and mediate cell attachment to insoluble substrates and degrade them to soluble products which are then absorbed. Cellulosome complexes are intricate, multi-enzyme machines, produced by many cellulolytic microorganisms. They are produced by microorganisms for efficient degradation of plant cell wall polysaccharides, notably cellulose, the most abundant organic polymer on Earth. The multiple subunits of cellulosomes are composed of numerous functional domains that interact with each other and with the cellulosic substrate. One of these subunits, a large glycoprotein "scaffoldin", is a distinctive class of non-catalytic scaffolding polypeptides. The scaffoldin subunit selectively integrates the various cellulases and xylanase subunits into the cohesive complex, by combining its cohesin domains with a typical dockerin domain present on each of the subunit enzymes. The scaffoldin of some cellulosomes, an example being that of Clostridium thermocellum, contains a carbohydrate-binding module that adheres cellulose to the cellulosomal complex.

<span class="mw-page-title-main">Glycoside hydrolase</span> Enzyme

Glycoside hydrolases catalyze the hydrolysis of glycosidic bonds in complex sugars. They are extremely common enzymes with roles in nature including degradation of biomass such as cellulose (cellulase), hemicellulose, and starch (amylase), in anti-bacterial defense strategies, in pathogenesis mechanisms and in normal cellular function. Together with glycosyltransferases, glycosidases form the major catalytic machinery for the synthesis and breakage of glycosidic bonds.

Xyloglucan is a hemicellulose that occurs in the primary cell wall of all vascular plants; however, all enzymes responsible for xyloglucan metabolism are found in Charophyceae algae. In many dicotyledonous plants, it is the most abundant hemicellulose in the primary cell wall. Xyloglucan binds to the surface of cellulose microfibrils and may link them together. It is the substrate of xyloglucan endotransglycosylase, which cuts and ligates xyloglucans, as a means of integrating new xyloglucans into the cell wall. It is also thought to be the substrate of alpha-expansin, which promotes cell wall enlargement.

Food chemistry is the study of chemical processes and interactions of all biological and non-biological components of foods. The biological substances include such items as meat, poultry, lettuce, beer, milk as examples. It is similar to biochemistry in its main components such as carbohydrates, lipids, and protein, but it also includes areas such as water, vitamins, minerals, enzymes, food additives, flavors, and colors. This discipline also encompasses how products change under certain food processing techniques and ways either to enhance or to prevent them from happening. An example of enhancing a process would be to encourage fermentation of dairy products with microorganisms that convert lactose to lactic acid; an example of preventing a process would be stopping the browning on the surface of freshly cut apples using lemon juice or other acidulated water.

CAZy is a database of Carbohydrate-Active enZYmes (CAZymes). The database contains a classification and associated information about enzymes involved in the synthesis, metabolism, and recognition of complex carbohydrates, i.e. disaccharides, oligosaccharides, polysaccharides, and glycoconjugates. Included in the database are families of glycoside hydrolases, glycosyltransferases, polysaccharide lyases, carbohydrate esterases, and non-catalytic carbohydrate-binding modules. The CAZy database also includes a classification of Auxiliary Activity redox enzymes involved in the breakdown of lignocellulose.

<span class="mw-page-title-main">Carbohydrate-binding module</span> (CBM) is a protein domain found in carbohydrate-active enzymes

In molecular biology, a carbohydrate-binding module (CBM) is a protein domain found in carbohydrate-active enzymes. The majority of these domains have carbohydrate-binding activity. Some of these domains are found on cellulosomal scaffoldin proteins. CBMs were previously known as cellulose-binding domains. CBMs are classified into numerous families, based on amino acid sequence similarity. There are currently 64 families of CBM in the CAZy database.

In molecular biology, glycoside hydrolase family 5 is a family of glycoside hydrolases EC 3.2.1., which are a widespread group of enzymes that hydrolyse the glycosidic bond between two or more carbohydrates, or between a carbohydrate and a non-carbohydrate moiety. A classification system for glycoside hydrolases, based on sequence similarity, has led to the definition of >100 different families. This classification is available on the CAZy web site, and also discussed at CAZypedia, an online encyclopedia of carbohydrate active enzymes.

In molecular biology, glycoside hydrolase family 26 is a family of glycoside hydrolases.

In molecular biology, glycoside hydrolase family 88 is a family of glycoside hydrolases.

In molecular biology, the X8 domain, is thought to play a role in targeting the plasmodesmata by providing it with structural support. The domain is able to do this since it contains signal sequences for a glycosylphosphatidylinositol (GPI) linkage to the extracellular face of the plasma membrane. This domain is involved in carbohydrate binding.

Beta porphyranase is an enzyme responsible for the degradation of porphyran, which composes the cell wall of red algae. So far only five β-porphyranases have been identified: PorA and PorB are found in the marine bacteria Zobellia galactinovirans. A wild-type porphyranase activity has been found in Pseudoalteromonas atlantica. BpGH16B and BpGH86A have been found in the human gut bacterium, Bacteroides plebeius, of Japanese individuals.

Microbiota-accessible carbohydrates (MACs) are carbohydrates that are resistant to digestion by a host's metabolism, and are made available for gut microbes, as prebiotics, to ferment or metabolize into beneficial compounds, such as short chain fatty acids. The term, ‘‘microbiota-accessible carbohydrate’’ contributes to a conceptual framework for investigating and discussing the amount of metabolic activity that a specific food or carbohydrate can contribute to a host's microbiota.

<span class="mw-page-title-main">Gideon Davies</span> Professor of Chemistry

Gideon John Davies is a Professor of Chemistry in the Structural Biology Laboratory (YSBL) at the University of York, UK. Davies is best known for his ground-breaking studies into carbohydrate-active enzymes, notably analysing the conformational and mechanistic basis for catalysis and applying this for societal benefit. In 2016 Davies was apppointed the Royal Society Ken Murray Research Professor at the University of York.

The α-mannan degradation Mannan which can be found in the cell wall of yeast has a particular chemical structure, and constitutes a food source since humans begun eating fermented foods several thousands of years ago. To determine whether the intake of yeast mannans through fermented foods has promoted specific adaptations of the human gut microbiota, an international team of researchers studied the ability of Bacteroides thetaiotaomicron to specifically degrade yeast mannans.

Bacteroides thetaiotaomicron is a species of bacterium of the genus Bacteroides. It is a gram-negative obligate anaerobe. It is one of the most common bacteria found in human gut microbiota and is also an opportunistic pathogen. Its genome contains numerous genes specialized in digestion of polysaccharides. It is often used in research as a model organism for functional studies of the human microbiota.

Phocaeicola plebeius, formerly Bacteroides plebeius, is a microbe found in the human gut, most often found in Japan natives. It is able to digest porphyran, a polysacchide from Porphyra seaweed (nori) that humans cannot digest on their own. The porphyranase-encoding gene Bp1689 is believed to have been derived from the microbe Zobellia galactanivorans via horizontal gene transfer, as part of a gene cluster containing other carbohydrate-active enzymes.

References

  1. 1 2 3 Harry J. Gilbert publications indexed by Google Scholar
  2. 1 2 Anon (2016). "Professor Harry Gilbert FRS". London: Royal Society. Archived from the original on 29 April 2016. One or more of the preceding sentences incorporates text from the royalsociety.org website where:
    "All text published under the heading 'Biography' on Fellow profile pages is available under Creative Commons Attribution 4.0 International License." -- "Royal Society Terms, conditions and policies". Archived from the original on 25 September 2015. Retrieved 9 March 2016.{{cite web}}: CS1 maint: bot: original URL status unknown (link)
  3. 1 2 "Professor Harry Gilbert: Strategic Research Adviser". Newcastle upon Tyne: Newcastle University. Archived from the original on 22 May 2016.
  4. Gilbert, Harry J. (1979). Studies on native and mutant forms of IMP dehydrogenase in Escherichia coli K12 (PhD thesis). University of Southampton. OCLC   59337956.
  5. Boraston, Alisdair B.; Bolam, David N.; Gilbert, Harry J.; Davies, Gideon J. (2004). "Carbohydrate-binding modules: fine-tuning polysaccharide recognition". Biochemical Journal. 382 (3): 769–781. doi:10.1042/BJ20040892. PMC   1133952 . PMID   15214846.
  6. Fontes, Carlos M.G.A.; Gilbert, Harry J. (2010). "Cellulosomes: Highly Efficient Nanomachines Designed to Deconstruct Plant Cell Wall Complex Carbohydrates". Annual Review of Biochemistry. 79 (1): 655–681. doi: 10.1146/annurev-biochem-091208-085603 . PMID   20373916.
  7. Gilbert, H. J.; Hazlewood, G. P. (1993). "Bacterial cellulases and xylanases". Journal of General Microbiology. 139 (2): 187–194. doi: 10.1099/00221287-139-2-187 .
  8. Eisen, Jonathan A.; Martens, Eric C.; Lowe, Elisabeth C.; Chiang, Herbert; Pudlo, Nicholas A.; Wu, Meng; McNulty, Nathan P.; Abbott, D. Wade; Henrissat, Bernard; Gilbert, Harry J.; Bolam, David N.; Gordon, Jeffrey I. (2011). "Recognition and Degradation of Plant Cell Wall Polysaccharides by Two Human Gut Symbionts". PLOS Biology . 9 (12): e1001221. doi: 10.1371/journal.pbio.1001221 . PMC   3243724 . PMID   22205877. Open Access logo PLoS transparent.svg
  9. Cuskin, Fiona; Lowe, Elisabeth C.; Temple, Max J.; Zhu, Yanping; Cameron, Elizabeth A.; Pudlo, Nicholas A.; Porter, Nathan T.; Urs, Karthik; Thompson, Andrew J.; Cartmell, Alan; Rogowski, Artur; Hamilton, Brian S.; Chen, Rui; Tolbert, Thomas J.; Piens, Kathleen; Bracke, Debby; Vervecken, Wouter; Hakki, Zalihe; Speciale, Gaetano; Munōz-Munōz, Jose L.; Day, Andrew; Peña, Maria J.; McLean, Richard; Suits, Michael D.; Boraston, Alisdair B.; Atherly, Todd; Ziemer, Cherie J.; Williams, Spencer J.; Davies, Gideon J.; Abbott, D. Wade; Martens, Eric C.; Gilbert, Harry J. (2015). "Human gut Bacteroidetes can utilize yeast mannan through a selfish mechanism". Nature . 517 (7533): 165–169. Bibcode:2015Natur.517..165C. doi:10.1038/nature13995. PMC   4978465 . PMID   25567280.
  10. "Beer and bread yeast-eating bacteria aid human health". York: University of York. Archived from the original on 17 April 2016.
  11. 1 2 Harry Gilbert's ORCID   0000-0003-3597-2347