Starch Digestion by Gut Bacteria: Crowdsourcing for Carbs

Trends in Microbiology, Год журнала: 2019, Номер 28(2), С. 95 - 108

Опубликована: Окт. 14, 2019

Язык: Английский

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Homologs of PROTEIN TARGETING TO STARCH Control Starch Granule Initiation in Arabidopsis Leaves

The Plant Cell, Год журнала: 2017, Номер 29(7), С. 1657 - 1677

Опубликована: Июль 1, 2017

The molecular mechanism that initiates the synthesis of starch granules is poorly understood. Here, we discovered two plastidial proteins involved in granule initiation Arabidopsis thaliana leaves. Both contain coiled coils and a family-48 carbohydrate binding module (CBM48) are homologs PROTEIN TARGETING TO STARCH (PTST) protein; thus, named them PTST2 PTST3. Chloroplasts mesophyll cells typically five to seven granules, but remarkably, most chloroplasts ptst2 mutants contained zero or one large granule. ptst3 had slight reduction number compared with wild type, while those double mutant even fewer than were larger similar morphology wild-type an aberrant morphology. Immunoprecipitation showed interacts SYNTHASE4 (SS4), which influences Overexpression resulted containing many small effect was dependent on presence SS4. Furthermore, isothermal titration calorimetry revealed CBM48 domain PTST2, essential for its function, long maltooligosaccharides. We propose PTST3 critical during initiation, as they bind deliver suitable maltooligosaccharide primers

Язык: Английский

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A Review of Starch Biosynthesis in Relation to the Building Block-Backbone Model

International Journal of Molecular Sciences, Год журнала: 2020, Номер 21(19), С. 7011 - 7011

Опубликована: Сен. 23, 2020

Starch is a water-insoluble polymer of glucose synthesized as discrete granules inside the stroma plastids in plant cells. reserves provide source carbohydrate for immediate growth and development, act long term carbon stores endosperms seed tissues next generation, making starch huge agricultural importance. The granule has highly complex hierarchical structure arising from combined actions large array enzymes well physicochemical self-assembly mechanisms. Understanding precise nature architecture, how both biological abiotic factors determine this fundamental practical This review outlines current knowledge architecture biosynthesis pathway relation to building block-backbone model structure. We highlight gaps our understanding synthesis starch, argue that takes accurate account structural biochemical data.

Язык: Английский

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Remarkable evolutionary relatedness among the enzymes and proteins from the α-amylase family

Cellular and Molecular Life Sciences, Год журнала: 2016, Номер 73(14), С. 2707 - 2725

Опубликована: Май 6, 2016

Язык: Английский

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Aspects and Recent Trends in Microbial α-Amylase: a Review

Applied Biochemistry and Biotechnology, Год журнала: 2021, Номер 193(8), С. 2649 - 2698

Опубликована: Март 14, 2021

Язык: Английский

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Microbial starch debranching enzymes: Developments and applications

Biotechnology Advances, Год журнала: 2021, Номер 50, С. 107786 - 107786

Опубликована: Июнь 18, 2021

Язык: Английский

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Applying the Sabatier Principle to Decipher the Surface-Structure-Dependent Catalysis of Different Starch Granules by Pullulanase

JACS Au, Год журнала: 2025, Номер unknown

Опубликована: Янв. 14, 2025

Interfacial enzyme catalysis is widespread in both nature and industry. Granular starch a sustainable abundant raw material for which rigorous correlation of the surface structure with enzymatic degradation lacking. Here pullulanase-catalyzed debranching 12 granular starches varying amylopectin contents branch chain lengths shown to present biphasic relationship characteristic Sabatier principle. Introducing normalization specific rate (v 0/E 0) by substrate-dependent constant C, related Arrhenius prefactor k cat, reveals that optimal activity according principle occurs at moderate substrate binding strength. The density pullulanase attack sites (kinΓmax), determined using combined conventional inverse Michaelis-Menten kinetics, was increased branching treatment. Medium kinΓmax length conferred highest depending on load. Correlation analysis demonstrated crystallinity, order, average influence affecting C constant. Therefore, should be considered together strength understand granules. could serve as diagnostic tool characterize performance substrates having different structures guide rational modification purposes.

Язык: Английский

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Starch granule initiation and morphogenesis—progress in Arabidopsis and cereals

Journal of Experimental Botany, Год журнала: 2018, Номер 70(3), С. 771 - 784

Опубликована: Ноя. 14, 2018

Starch, the major storage carbohydrate in plants, is synthesized plastids as semi-crystalline, insoluble granules. Many organs and cell types accumulate starch at some point during their development maturation. The biosynthesis of polymers, amylopectin amylose, relatively well understood mostly conserved between species. However, we are only beginning to understand mechanism by which granules initiated, factors that control number per plastid size/shape Here, review recent progress understanding granule initiation morphogenesis. In Arabidopsis, requires several newly discovered proteins with specific locations within chloroplast, also on availability maltooligosaccharides act primers for initiation. We describe biogenesis endosperm cereal grains—within there large interspecies variation patterns morphology. Investigating whether this diversity results from differences species functions known proteins, and/or presence novel, unidentified a promising area future research. Expanding our knowledge these areas will lead new strategies improving quality crops modifying size shape vivo.

Язык: Английский

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Novel carbohydrate binding modules in the surface anchored α‐amylase of Eubacterium rectale provide a molecular rationale for the range of starches used by this organism in the human gut

Molecular Microbiology, Год журнала: 2017, Номер 107(2), С. 249 - 264

Опубликована: Ноя. 15, 2017

Summary Gut bacteria recognize accessible glycan substrates within a complex environment. Carbohydrate binding modules (CBMs) of cell surface glycoside hydrolases often drive to the target substrate. Eubacterium rectale , an important butyrate‐producing organism in gut, consumes limited range substrates, including starch. Host consumption resistant starch increases abundance E. intestine, likely because it successfully captures products degradation by other bacteria. Here, we demonstrate that wall anchored starch‐degrading α‐amylase, Amy13K harbors five CBMs all with differing specificities. Intriguingly these efficiently bind both regular and high amylose corn (a type starch), but have almost no affinity for potato (another starch). Removal from reduces activity level enzyme toward starches ∼40‐fold, down starch, suggesting facilitate on allow its utilization vivo . The specificity provides molecular rationale why is able only use certain types without aid organisms.

Язык: Английский

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Enhanced extracellular pullulanase production in Bacillus subtilis using protease-deficient strains and optimal feeding

Applied Microbiology and Biotechnology, Год журнала: 2018, Номер 102(12), С. 5089 - 5103

Опубликована: Апрель 20, 2018

Язык: Английский

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