6E67

Structure of beta2 adrenergic receptor fused to a Gs peptide

External Resource: Annotation

Domain Annotation: SCOP2 Classification
Domain Annotation: ECOD Classification
Protein Family Annotation
Gene Ontology: Gene Product Annotation
InterPro: Protein Family Classification
Pharos: Disease Associations
Membrane Protein Annotation: OPM
Membrane Protein Annotation: PDBTM
Membrane Protein Annotation: MemProtMD
Membrane Protein Annotation: mpstruc

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
A	SCOP2B Superfamily	Lysozyme-like	8093428	3001879	SCOP2B (2022-06-29)
A	SCOP2B Superfamily	G protein-coupled receptor-like	8091150	3000473	SCOP2B (2022-06-29)
B	SCOP2 Family	Phage lysozyme	8093427	4000895	SCOP2 (2022-06-29)
B	SCOP2 Superfamily	Lysozyme-like	8093428	3001879	SCOP2 (2022-06-29)
B	SCOP2B Superfamily	G protein-coupled receptor-like	8091150	3000473	SCOP2B (2022-06-29)

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A	7tm_1_3	e6e67A1	A: alpha bundles	X: Family A G protein-coupled receptor-like (From Topology)	H: Family A G protein-coupled receptor-like (From Topology)	T: Family A G protein-coupled receptor-like	F: 7tm_1_3	ECOD (1.6)
A	Phage_lysozyme_2	e6e67A2	A: a+b complex topology	X: Lysozyme-like (From Homology)	H: Lysozyme-like	T: Lysozyme-like	F: Phage_lysozyme_2	ECOD (1.6)
B	7tm_1_3	e6e67B1	A: alpha bundles	X: Family A G protein-coupled receptor-like (From Topology)	H: Family A G protein-coupled receptor-like (From Topology)	T: Family A G protein-coupled receptor-like	F: 7tm_1_3	ECOD (1.6)
B	Phage_lysozyme_2	e6e67B2	A: a+b complex topology	X: Lysozyme-like (From Homology)	H: Lysozyme-like	T: Lysozyme-like	F: Phage_lysozyme_2	ECOD (1.6)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A, B	PF00503	G-protein alpha subunit (G-alpha)	G-protein alpha subunit	G proteins couple receptors of extracellular signals to intracellular signaling pathways. The G protein alpha subunit binds guanyl nucleotide and is a weak GTPase. A set of residues that are unique to G-alpha as compared to its ancestor the Arf-like ...	G proteins couple receptors of extracellular signals to intracellular signaling pathways. The G protein alpha subunit binds guanyl nucleotide and is a weak GTPase. A set of residues that are unique to G-alpha as compared to its ancestor the Arf-like family form a ring of residues centered on the nucleotide binding site [3]. A Ggamma is found fused to an inactive Galpha in the Dictyostelium protein gbqA [3].	Domain
A, B	PF00959	Phage lysozyme (Phage_lysozyme)	Phage lysozyme	This family includes lambda phage lysozyme and E. coli endolysin.	Domain
A, B	PF00001	7 transmembrane receptor (rhodopsin family) (7tm_1)	7 transmembrane receptor (rhodopsin family)	-	Family

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A, B	Beta-2 adrenergic receptor,Endolysin,Guanine nucleotide-binding protein G(s) subunit alpha isoforms short,Beta-2 adrenergic receptor chimera	amide binding amyloid-beta binding binding peptide binding protein binding enzyme binding adenylate cyclase binding G protein-coupled amine receptor activity molecular transducer activity beta2-adrenergic receptor activity G protein-coupled receptor activity transmembrane signaling receptor activity signaling receptor activity beta-adrenergic receptor activity amide binding amyloid-beta binding binding peptide binding protein binding enzyme binding adenylate cyclase binding G protein-coupled amine receptor activity molecular transducer activity beta2-adrenergic receptor activity G protein-coupled receptor activity transmembrane signaling receptor activity signaling receptor activity beta-adrenergic receptor activity adrenergic receptor activity protein-containing complex binding potassium channel regulator activity channel regulator activity ion channel regulator activity molecular function regulator activity transporter regulator activity identical protein binding protein homodimerization activity protein dimerization activity cation binding ion binding catecholamine binding organic cyclic compound binding norepinephrine binding small molecule binding guanyl nucleotide binding GTP binding nucleotide binding guanyl ribonucleotide binding purine ribonucleotide binding purine ribonucleoside triphosphate binding nucleoside phosphate binding purine nucleotide binding anion binding heterocyclic compound binding carbohydrate derivative binding ribonucleotide binding D1 dopamine receptor binding signaling receptor binding G protein-coupled receptor binding dopamine receptor binding G-protein beta/gamma-subunit complex binding enzyme regulator activity cyclase regulator activity enzyme activator activity cyclase activator activity molecular function activator activity adenylate cyclase regulator activity adenylate cyclase activator activity metal ion binding pyrophosphatase activity GTPase activity ribonucleoside triphosphate phosphatase activity hydrolase activity, acting on acid anhydrides, in phosphorus-containing anhydrides hydrolase activity hydrolase activity, acting on acid anhydrides catalytic activity hydrolase activity, acting on glycosyl bonds peptidoglycan muralytic activity hydrolase activity, hydrolyzing O-glycosyl compounds lysozyme activity	multicellular organismal process response to nutrient levels multicellular organismal-level homeostasis response to stimulus response to dietary excess homeostatic process diet induced thermogenesis metabolic process energy homeostasis adaptive thermogenesis cellular response to stimulus regulation of localization regulation of cellular process signaling multicellular organismal process response to nutrient levels multicellular organismal-level homeostasis response to stimulus response to dietary excess homeostatic process diet induced thermogenesis metabolic process energy homeostasis adaptive thermogenesis cellular response to stimulus regulation of localization regulation of cellular process signaling transport regulation of signaling receptor activity monoatomic ion transmembrane transport regulation of AMPA receptor activity positive regulation of biological process regulation of transmembrane transporter activity regulation of signal transduction regulation of monoatomic ion transmembrane transport cell communication regulation of transporter activity positive regulation of molecular function localization positive regulation of monoatomic ion transport positive regulation of transmembrane transport monoatomic ion transport positive regulation of monoatomic ion transmembrane transport signal transduction positive regulation of cellular process regulation of monoatomic ion transmembrane transporter activity regulation of biological process regulation of signaling regulation of transport positive regulation of signaling receptor activity regulation of monoatomic ion transport biological regulation establishment of localization transmembrane transport regulation of molecular function positive regulation of AMPA receptor activity regulation of transmembrane transport positive regulation of transport regulation of response to stimulus positive regulation of transporter activity regulation of neurotransmitter receptor activity positive regulation of ion transmembrane transporter activity regulation of cell communication cellular process response to stress response to abiotic stimulus response to cold response to temperature stimulus regulation of developmental process regulation of biomineral tissue development regulation of bone mineralization positive regulation of ossification positive regulation of developmental process multicellular organism development positive regulation of biomineral tissue development ossification anatomical structure development biomineral tissue development regulation of multicellular organismal process developmental process regulation of multicellular organismal development bone mineralization animal organ development tissue development positive regulation of bone mineralization positive regulation of multicellular organismal process regulation of ossification regulation of multicellular organism growth regulation of growth regulation of developmental growth negative regulation of multicellular organism growth developmental growth negative regulation of developmental process growth negative regulation of biological process multicellular organism growth negative regulation of developmental growth negative regulation of growth negative regulation of multicellular organismal process adenylate cyclase-activating adrenergic receptor signaling pathway adenylate cyclase-activating G protein-coupled receptor signaling pathway adrenergic receptor signaling pathway adenylate cyclase-modulating G protein-coupled receptor signaling pathway G protein-coupled receptor signaling pathway positive regulation of cell communication positive regulation of signal transduction intracellular signal transduction positive regulation of response to stimulus regulation of intracellular signal transduction positive regulation of intracellular signal transduction regulation of protein kinase A signaling protein kinase A signaling positive regulation of protein kinase A signaling positive regulation of signaling fat cell differentiation cellular developmental process brown fat cell differentiation cell differentiation positive regulation of phosphorylation regulation of catalytic activity regulation of transferase activity positive regulation of phosphate metabolic process regulation of primary metabolic process positive regulation of protein serine/threonine kinase activity positive regulation of metabolic process regulation of phosphate metabolic process phosphate-containing compound metabolic process positive regulation of macromolecule metabolic process phosphorus metabolic process protein modification process positive regulation of protein phosphorylation protein phosphorylation positive regulation of phosphorus metabolic process phosphorylation cellular metabolic process regulation of protein metabolic process regulation of cellular metabolic process primary metabolic process positive regulation of kinase activity regulation of kinase activity macromolecule modification regulation of protein serine/threonine kinase activity regulation of phosphorus metabolic process macromolecule metabolic process regulation of metabolic process regulation of protein modification process regulation of protein phosphorylation positive regulation of protein metabolic process positive regulation of cellular metabolic process positive regulation of protein modification process organic substance metabolic process protein metabolic process positive regulation of protein kinase activity organonitrogen compound metabolic process positive regulation of transferase activity positive regulation of catalytic activity regulation of protein kinase activity regulation of macromolecule metabolic process regulation of phosphorylation positive regulation of adenylate cyclase activity positive regulation of cyclase activity regulation of lyase activity activation of adenylate cyclase activity regulation of adenylate cyclase activity regulation of cyclase activity positive regulation of lyase activity system process regulation of system process muscle contraction muscle system process regulation of muscle system process negative regulation of muscle contraction smooth muscle contraction regulation of smooth muscle contraction regulation of muscle contraction negative regulation of smooth muscle contraction regulation of cAMP-dependent protein kinase activity positive regulation of cAMP-dependent protein kinase activity positive regulation of macromolecule biosynthetic process nucleobase-containing compound metabolic process DNA-templated transcription regulation of RNA metabolic process transcription by RNA polymerase II organic substance biosynthetic process regulation of nucleobase-containing compound metabolic process regulation of transcription by RNA polymerase II positive regulation of nucleobase-containing compound metabolic process positive regulation of transcription by RNA polymerase II positive regulation of RNA metabolic process organic cyclic compound metabolic process regulation of gene expression biosynthetic process organic cyclic compound biosynthetic process regulation of macromolecule biosynthetic process regulation of DNA-templated transcription positive regulation of DNA-templated transcription cellular biosynthetic process RNA metabolic process RNA biosynthetic process nucleic acid biosynthetic process positive regulation of biosynthetic process regulation of RNA biosynthetic process regulation of biosynthetic process nucleobase-containing compound biosynthetic process gene expression macromolecule biosynthetic process nucleic acid metabolic process regulation of cellular biosynthetic process positive regulation of RNA biosynthetic process positive regulation of cellular biosynthetic process tissue remodeling bone remodeling anatomical structure homeostasis tissue homeostasis bone resorption cell surface receptor protein tyrosine kinase signaling pathway cellular component biogenesis cellular component assembly activation of transmembrane receptor protein tyrosine kinase activity activation of protein kinase activity cellular component organization protein-containing complex assembly cellular component organization or biogenesis enzyme-linked receptor protein signaling pathway cell surface receptor signaling pathway protein-containing complex organization import into cell receptor-mediated endocytosis endocytosis vesicle-mediated transport cellular localization endosome to lysosome transport intracellular transport lysosomal transport establishment of localization in cell vacuolar transport negative adaptation of signaling pathway negative regulation of signaling desensitization of G protein-coupled receptor signaling pathway negative regulation of G protein-coupled receptor signaling pathway negative regulation of cell communication regulation of protein binding desensitization of G protein-coupled receptor signaling pathway by arrestin negative regulation of cellular process regulation of G protein-coupled receptor signaling pathway negative regulation of response to stimulus negative regulation of binding regulation of binding negative regulation of molecular function negative regulation of signal transduction negative regulation of protein binding adaptation of signaling pathway positive regulation of organelle organization catabolic process regulation of cellular component organization positive regulation of cellular component organization regulation of autophagosome maturation macroautophagy autophagy protein-containing complex disassembly regulation of autophagy regulation of protein-containing complex disassembly cellular catabolic process autophagosome maturation positive regulation of macroautophagy process utilizing autophagic mechanism positive regulation of protein-containing complex disassembly cellular component disassembly positive regulation of autophagy regulation of catabolic process positive regulation of autophagosome maturation regulation of organelle organization positive regulation of catabolic process organelle organization regulation of macroautophagy regulation of cellular catabolic process positive regulation of cellular catabolic process lipophagy positive regulation of lipophagy regulation of lipophagy response to psychosocial stress regulation of cold-induced thermogenesis cold-induced thermogenesis temperature homeostasis positive regulation of cold-induced thermogenesis intracellular signaling cassette positive regulation of MAPK cascade regulation of MAPK cascade MAPK cascade regulation of tube diameter regulation of systemic arterial blood pressure mediated by a chemical signal regulation of blood pressure regulation of tube size norepinephrine-epinephrine-mediated vasodilation involved in regulation of systemic arterial blood pressure negative regulation of blood pressure regulation of systemic arterial blood pressure by norepinephrine-epinephrine regulation of systemic arterial blood pressure circulatory system process negative regulation of systemic arterial blood pressure vascular process in circulatory system regulation of biological quality blood vessel diameter maintenance vasodilation blood circulation regulation of anatomical structure size cellular response to nitrogen compound response to organic substance response to organonitrogen compound response to endogenous stimulus response to oxygen-containing compound response to nitrogen compound cellular response to amyloid-beta cellular response to oxygen-containing compound cellular response to endogenous stimulus cellular response to chemical stimulus cellular response to organonitrogen compound response to chemical cellular response to organic substance response to amyloid-beta regulation of sodium ion transport metal ion transport monoatomic cation transport regulation of metal ion transport sodium ion transport heat generation regulation of postsynaptic membrane potential modulation of chemical synaptic transmission positive regulation of excitatory postsynaptic potential chemical synaptic transmission, postsynaptic synaptic signaling modulation of excitatory postsynaptic potential mini excitatory postsynaptic potential trans-synaptic signaling nervous system process cell-cell signaling chemical synaptic transmission regulation of nervous system process regulation of mini excitatory postsynaptic potential positive regulation of mini excitatory postsynaptic potential regulation of trans-synaptic signaling anterograde trans-synaptic signaling excitatory postsynaptic potential regulation of membrane potential epithelium development ectodermal placode morphogenesis epidermis development molting cycle process hair cycle hair follicle placode formation ectodermal placode formation anatomical structure morphogenesis skin development skin epidermis development hair follicle development molting cycle anatomical structure formation involved in morphogenesis ectodermal placode development hair cycle process sensory perception of chemical stimulus sensory perception sensory perception of smell positive regulation of hydrolase activity regulation of hydrolase activity regulation of GTPase activity positive regulation of GTPase activity skeletal system development bone development system development cAMP-mediated signaling positive regulation of cAMP-mediated signaling regulation of cAMP-mediated signaling regulation of body fluid levels wound healing homotypic cell-cell adhesion cell activation hemostasis platelet aggregation blood coagulation cell adhesion cell-cell adhesion coagulation response to wounding platelet activation cognition response to ketone response to prostaglandin response to lipid response to hormone response to prostaglandin E cellular response to ketone cellular response to hormone stimulus response to alcohol cellular response to prostaglandin stimulus cellular response to prostaglandin E stimulus cellular response to alcohol cellular response to lipid response to dopamine dopamine receptor signaling pathway cellular response to dopamine response to monoamine response to catecholamine adenylate cyclase-activating dopamine receptor signaling pathway cellular response to catecholamine stimulus response to organic cyclic compound cellular response to organic cyclic compound cellular response to monoamine stimulus biological process involved in interspecies interaction between organisms response to other organism defense response response to external stimulus response to biotic stimulus defense response to bacterium defense response to other organism response to bacterium response to external biotic stimulus organonitrogen compound catabolic process carbohydrate derivative catabolic process peptidoglycan catabolic process glycosaminoglycan metabolic process carbohydrate derivative metabolic process aminoglycan catabolic process macromolecule catabolic process glycosaminoglycan catabolic process aminoglycan metabolic process peptidoglycan metabolic process organic substance catabolic process symbiont-mediated cytolysis of host cell viral life cycle disruption of cell in another organism cytolysis biological process involved in interaction with host biological process involved in symbiotic interaction viral release from host cell by cytolysis disruption of cellular anatomical structure in another organism exit from host cell viral process cytolysis in another organism viral release from host cell disruption of anatomical structure in another organism symbiont-mediated killing of host cell killing of cells of another organism cell killing disruption of plasma membrane integrity in another organism cell wall organization or biogenesis cell wall macromolecule catabolic process cell wall macromolecule metabolic process	membrane cellular anatomical entity membrane-bounded organelle intracellular anatomical structure dense core granule intracellular vesicle intracellular membrane-bounded organelle endomembrane system intracellular organelle cytoplasmic vesicle organelle secretory granule secretory vesicle cytoplasm membrane cellular anatomical entity membrane-bounded organelle intracellular anatomical structure dense core granule intracellular vesicle intracellular membrane-bounded organelle endomembrane system intracellular organelle cytoplasmic vesicle organelle secretory granule secretory vesicle cytoplasm vesicle neuronal dense core vesicle bounding membrane of organelle vesicle membrane clathrin-coated vesicle endocytic vesicle membrane coated vesicle endocytic vesicle clathrin-coated vesicle membrane clathrin-coated endocytic vesicle membrane clathrin-coated endocytic vesicle cytoplasmic vesicle membrane coated vesicle membrane organelle membrane protein-containing complex receptor complex Golgi apparatus endosome membrane endosome cell periphery apical part of cell plasma membrane plasma membrane region apical plasma membrane lytic vacuole vacuole lysosome early endosome nucleus extrinsic component of plasma membrane catalytic complex plasma membrane protein complex cytoplasmic side of membrane membrane protein complex heterotrimeric G-protein complex side of membrane cytoplasmic side of plasma membrane GTPase complex extrinsic component of membrane extrinsic component of cytoplasmic side of plasma membrane extracellular exosome extracellular vesicle extracellular organelle extracellular region extracellular space extracellular membrane-bounded organelle cytosol Golgi apparatus subcompartment organelle subcompartment trans-Golgi network membrane trans-Golgi network host cellular component host intracellular part host cell cytoplasm host cell part host intracellular region

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A, B	IPR000332	Beta 2 adrenoceptor	Family
A, B	IPR000276	G protein-coupled receptor, rhodopsin-like	Family
A, B	IPR002233	Adrenoceptor family	Family
A, B	IPR017452	GPCR, rhodopsin-like, 7TM	Domain
A, B	IPR001019	Guanine nucleotide binding protein (G-protein), alpha subunit	Family
A, B	IPR011025	G protein alpha subunit, helical insertion	Homologous Superfamily
A, B	IPR027417	P-loop containing nucleoside triphosphate hydrolase	Homologous Superfamily
A, B	IPR000367	G-protein alpha subunit, group S	Family
A, B	IPR001165	T4-type lysozyme	Family
A, B	IPR034690	Endolysin T4 type	Family
A, B	IPR002196	Glycoside hydrolase, family 24	Family
A, B	IPR023347	Lysozyme domain superfamily	Homologous Superfamily
A, B	IPR023346	Lysozyme-like domain superfamily	Homologous Superfamily

Pharos: Disease Associations Pharos Homepage Annotation

Chains	Drug Target	Associated Disease
A, B	Pharos: P63092	asthma cardiomyopathy dilated cardiomyopathy Ventricular Dysfunction, Left prostate cancer HIV infectious disease nervous system disorder chronic obstructive pulmonary disease AIDS dementia complex potassium deficiency disease lung disease obesity disorder ovarian cancer essential tremor bipolar disorder asthma cardiomyopathy dilated cardiomyopathy Ventricular Dysfunction, Left prostate cancer HIV infectious disease nervous system disorder chronic obstructive pulmonary disease AIDS dementia complex potassium deficiency disease lung disease obesity disorder ovarian cancer essential tremor bipolar disorder peripheral nervous system disease familial hyperlipidemia breast fibroadenoma lung adenocarcinoma cardiac arrest glaucoma hereditary diffuse gastric adenocarcinoma pulmonary emphysema hypertensive disorder inherited susceptibility to asthma ocular hypertension dilated cardiomyopathy 1A atrial fibrillation Parkinson disease breast cancer peripheral neuropathy fibromyalgia vasomotor rhinitis bronchiectasis gastric cancer viral encephalitis lung cancer malignant colon neoplasm seasonal allergic rhinitis hypertrophic cardiomyopathy allergic rhinitis myocardial ischemia non-small cell lung carcinoma open-angle glaucoma dry eye syndrome intrinsic asthma atrioventricular block osteosarcoma B-cell chronic lymphocytic leukemia breast carcinoma bronchitis gastric neoplasm hemangioma malignant ependymoma psoriasis medulloblastoma rhinitis hyperlipidemia allergic asthma monogenic obesity common cold anaphylaxis coronary artery disease atopic conjunctivitis ductal breast carcinoma in situ invasive ductal breast carcinoma autism McCune-Albright syndrome progressive osseous heteroplasia pseudohypoparathyroidism type 1A pseudohypoparathyroidism polycystic ovary syndrome acromegaly pseudohypoparathyroidism type 1B cholangiocarcinoma pseudopseudohypoparathyroidism precocious puberty obesity disorder substance withdrawal syndrome pseudohypoaldosteronism ACTH-independent macronodular adrenal hyperplasia 1 neuroblastoma brachydactyly intellectual disability pseudohypoparathyroidism type 1C Cafe-au-Lait Spots hypertensive disorder monostotic fibrous dysplasia cancer colorectal cancer intrahepatic cholangiocarcinoma endocrine system disease autosomal dominant pseudohypoaldosteronism type 1 sex cord-stromal tumor Cushing disease due to pituitary adenoma adrenal gland cancer growth hormone-producing pituitary gland adenoma pilocytic astrocytoma tuberculosis interstitial cystitis congenital hypothyroidism large cell medulloblastoma Cushing syndrome malignant glioma acquired metabolic disease progressive supranuclear palsy medulloblastoma pseudohypoaldosteronism type 2 ductal breast carcinoma in situ adenoma adrenal gland hyperfunction osteitis fibrosa ovarian cancer atypical teratoid rhabdoid tumor pancreatic intraductal papillary-mucinous neoplasm with low grade dysplasia bile duct cancer testicular sex cord-stromal neoplasm pituitary cancer craniosynostosis Cushing syndrome due to macronodular adrenal hyperplasia fibrodysplasia ossificans progressiva oligodendroglioma gallstones osteogenesis imperfecta schizophrenia growth hormone secreting pituitary adenoma 1 pancreatic intraductal papillary-mucinous carcinoma hemorrhagic disease Pick disease pituitary gland adenoma congenital anemia invasive ductal breast carcinoma malignant ependymoma cystic fibrosis ACTH-dependent Cushing syndrome pseudohypoaldosteronism type 1 endogenous depression neurofibromatosis type 1 fibrous dysplasia Alzheimer disease glioblastoma osteosarcoma astrocytic tumor pancreatic intraductal papillary-mucinous neoplasm autosomal recessive pseudohypoaldosteronism type 1

Membrane Protein Annotation: OPM OPM Database Homepage

Chains	External Link	Type	Class	Superfamily	Family
A, B	OPM	Transmembrane	Alpha-helical polytopic	Rhodopsin-like receptors and pumps	G-protein coupled receptors, family A

Membrane Protein Annotation: PDBTM PDBTM Database Homepage

Chains	External Link	Comment
A, B	PDBTM	Annotated as membrane protein by PDBTM

Membrane Protein Annotation: MemProtMD MemProtMD Database Homepage

Chains	External Link	Comment
A, B	MemProtMD	Annotated as membrane protein by MemProtMD

Membrane Protein Annotation: mpstruc mpstruc Database Homepage

Chains	Resource Link	Group	Subgroup	Protein
A, B	mpstruc	TRANSMEMBRANE PROTEINS: ALPHA-HELICAL	G Protein-Coupled Receptors: Class A	β₂ adrenergic receptor fused to a Gs peptide

RCSB PDB Core Operations are funded by the National Science Foundation (DBI-1832184), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM133198.