Abstract:
:The recognition of carrier proteins by multiple catalytic partners occurs in every cycle of chain elongation in the biosynthesis of fatty acids and of the pharmacologically important polyketide and nonribosomal peptide natural products. To dissect the features of carrier proteins that determine specific recognition at distinct points in assembly lines, we have used the two-module Escherichia coli enterobactin synthetase as a model system. Using an entB knockout strain, we developed a selection for growth on iron-limiting medium to evolve aryl carrier protein domains. The aryl carrier proteins from VibB of Vibrio cholerae vibriobactin and HMWP2 of Yersinia pestis yersiniabactin assembly lines were evolved by random mutagenesis to support growth under selection conditions, yielding a convergent set of mutations. Subsequent in vitro biochemical characterizations with partner enzymes EntE, EntF, and Sfp on the evolved VibB aryl carrier protein revealed a approximately 500-fold improvement in reconstituted enterobactin production activity. Mechanistic characterization identified three distinct specific recognition surfaces of VibBArCP for three catalytic partners in enterobactin biosynthesis. Our results suggest that heterologous carrier protein interactions can be engineered with a small number of mutations given a suitable selection scheme and provide insights for reprogramming nonribosomal peptide biosynthesis.
journal_name
Proc Natl Acad Sci U S Aauthors
Zhou Z,Lai JR,Walsh CTdoi
10.1073/pnas.0705122104subject
Has Abstractpub_date
2007-07-10 00:00:00pages
11621-6issue
28eissn
0027-8424issn
1091-6490pii
0705122104journal_volume
104pub_type
杂志文章abstract::The skeletal muscle sarcoplasmic reticulum (SR) was investigated for the presence of well-known endoplasmic reticulum (ER) markers: the lumenal protein BiP and a group of membrane proteins recognized by an antibody raised against ER membrane vesicles. Western blots of SR fractions revealed the presence of BiP in fast-...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.89.13.6142
更新日期:1992-07-01 00:00:00
abstract::The proinflammatory cytokine interleukin 1 (IL-1) activates the transcription of many genes encoding acute phase and proinflammatory proteins, a function mediated primarily by the transcription factor NF-kappaB. An early IL-1 signaling event is the recruitment of the Ser/Thr kinase IRAK to the type I IL-1 receptor (IL...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.94.24.12829
更新日期:1997-11-25 00:00:00
abstract::The feasibility of long-term information storage by brain type II Ca2+/calmodulin-dependent protein kinase molecules is explored. Recent evidence indicates that this protein has switch-like properties. Equations are derived showing that a single kinase holoenzyme could form a bistable switch having the stability neces...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.85.14.5320
更新日期:1988-07-01 00:00:00
abstract::A mitochondrial gene from Saccharomyces cerevisiae encoding a hydrophobic membrane protein, subunit 8 of the F0/F1-type mitochondrial ATPase complex, has been functionally replaced by an artificial nuclear gene specifying an imported version of this protein. The experiments reported here utilized a multicopy expressio...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.85.7.2091
更新日期:1988-04-01 00:00:00
abstract::A specific high-affinity receptor for leukotriene C4 (LTC4) has been identified on segments of longitudinal smooth muscle from guinea pig ileum, in disrupted cells obtained from the ileal segments, and in subcellular fractions enriched for mitochondrial membranes and plasma membranes, respectively. Specific [3H]LTC4 b...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.81.14.4529
更新日期:1984-07-01 00:00:00
abstract::The functional architecture of mammalian visual cortex has been elucidated in impressive detail by experimental work of the past 20-25 years. The origin of many of the salient features of this architecture, however, has remained unexplained. This paper is the first of three (the others will appear in subsequent issues...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.83.19.7508
更新日期:1986-10-01 00:00:00
abstract::The amino acid sequence for chicken smooth muscle myosin light chain kinase (smMLCK) was deduced from a full-length cDNA. This has allowed definition of both the complete sequence of the inactive 64-kDa proteolytic fragment, which contains the pseudosubstrate autoregulatory sequence, and of the active 61-kDa Ca2+/calm...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.87.6.2284
更新日期:1990-03-01 00:00:00
abstract::Type I cadherin cell-adhesion proteins are similar in sequence and structure and yet are different enough to mediate highly specific cell-cell recognition phenomena. It has previously been shown that small differences in the homophilic and heterophilic binding affinities of different type I family members can account ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1416737111
更新日期:2014-10-07 00:00:00
abstract::The Drosophila melanogaster urate oxidase (UO)-encoding gene is expressed in the third-instar larva and adult. In contrast, the Drosophila pseudoobscura UO gene is only expressed in the adult, whereas the Drosophila virilis UO gene is expressed only in the third-instar larva. UO activity in these three Drosophila spec...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.88.13.5489
更新日期:1991-07-01 00:00:00
abstract::The toxicological significance of exposures to synthetic chemicals is examined in the context of exposures to naturally occurring chemicals. We calculate that 99.99% (by weight) of the pesticides in the American diet are chemicals that plants produce to defend themselves. Only 52 natural pesticides have been tested in...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.87.19.7777
更新日期:1990-10-01 00:00:00
abstract::We report the heavy chain variable region sequences from the cDNAs of five previously described monoclonal cell lines producing human antibodies specific for the human immunodeficiency virus type 1 and detail the molecular characteristics, germ-line origins, and extent of somatic mutation among these antibodies. Three...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.88.17.7783
更新日期:1991-09-01 00:00:00
abstract::Although inappropriate activation of the Wnt/beta-catenin pathway has been implicated in the development of hepatocellular carcinoma (HCC), the role of this signaling in liver carcinogenesis remains unclear. To investigate this issue, we constructed a mutant mouse strain, Apc(lox/lox), in which exon 14 of the tumor-su...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0404761101
更新日期:2004-12-07 00:00:00
abstract::The multifunctional Ca2+/calmodulin-dependent protein kinase purified from rat brain cytosol undergoes an intramolecular self-phosphorylation or autophosphorylation. Autophosphorylation produces two strikingly different effects on kinase activity that are dependent on the level of ATP used in the reaction. At low but ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.83.24.9497
更新日期:1986-12-01 00:00:00
abstract::Acanthamoeba castellanii contains two enzymes, myosins IA and IB, that exhibit the catalytic properties of a myosin but possess very unusual physical properties, the most striking of which are their single, low molecular weight heavy chain, their globular shape, and their inability to form bipolar filaments. We have n...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.83.13.4655
更新日期:1986-07-01 00:00:00
abstract::Quantitative immunohistochemical analysis of the sphenopalatine ganglion in normal cats revealed that virtually all ganglion cells (98.5%) were immunoreactive to vasoactive intestinal polypeptide (VIP). After surgical removal of this ganglion, the content of both VIP and choline acetyltransferase (acetyl-CoA:choline O...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.78.8.5255
更新日期:1981-08-01 00:00:00
abstract::ADP ribosylation factor (ARF) is a small guanosine triphosphate (GTP)-binding protein that regulates the binding of coat proteins to membranes and is required for several stages of vesicular transport. ARF also stimulates phospholipase D (PLD) activity, which can alter the lipid content of membranes by conversion of p...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.92.11.4952
更新日期:1995-05-23 00:00:00
abstract::Selection is widely accepted as the principal force shaping phenotypic variation within populations. Its importance in speciation and macroevolution has been questioned, however, because phenotypic differences between species or higher taxa sometimes appear to be nonadaptive. Here, we use the quantitative trait locus ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.192360899
更新日期:2002-09-17 00:00:00
abstract::The virulent properties of the common human and livestock pathogen Clostridium perfringens are attributable to a formidable battery of toxins. Among these are a number of large and highly modular carbohydrate-active enzymes, including the mu-toxin and sialidases, whose catalytic properties are consistent with degradat...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0803154105
更新日期:2008-08-26 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0903186107
更新日期:2010-01-12 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.79.9.2885
更新日期:1982-05-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.85.5.1384
更新日期:1988-03-01 00:00:00
abstract::The term amyloid defines a group of proteins that aggregate into plaques or fibers. Amyloid fibers gained their fame mostly due to their relation with neurodegenerative diseases in humans. However, secreted by lower organisms, such as bacteria and fungi, amyloid fibers play a functional role: for example, when they se...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1908782116
更新日期:2019-11-05 00:00:00
abstract::The DNA end-joining protein Ku70 is one of several proteins that inhibit apoptosis by sequestering the proapoptotic factor Bax from the mitochondria. However, the molecular mechanism underlying Ku70-dependent inhibition of Bax is not fully understood. Here, we show that the absence of Ku70 results in the accumulation ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0706700105
更新日期:2008-04-01 00:00:00
abstract::Although tumor necrosis factor (TNF) initially came to prominence because of its anti-tumor activity, most attention is now focused on its proinflammatory actions. TNF appears to play a critical role in both early and late events involved in inflammation, from localizing the noxious agent and amplifying the cellular a...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.94.15.8093
更新日期:1997-07-22 00:00:00
abstract::The free radicals nitric oxide and superoxide anion react to form peroxynitrite (ONOO-), a highly toxic oxidant species. In vivo formation of ONOO- has been demonstrated in shock and inflammation. Herein we provide evidence that cytotoxicity in cells exposed to ONOO- is mediated by DNA strand breakage and the subseque...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.93.5.1753
更新日期:1996-03-05 00:00:00
abstract::Expansion of polyglutamine repeats in several unrelated proteins causes neurodegenerative diseases with distinct but related pathologies. To provide a model system for investigating common pathogenic features, we have examined the behavior of polyglutamine expansions expressed in Caenorhabditis elegans. The expression...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.100107297
更新日期:2000-05-23 00:00:00
abstract::We have studied ten phenotypically similar patients with complete androgen insensitivity. All of the patients tested had significantly elevated serum luteinizing hormone and plasma androgens within or above the normal adult male range. On the basis of specific dihydrotestosterone binding by skin fibroblasts, we identi...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.73.3.891
更新日期:1976-03-01 00:00:00
abstract::Insulin and insulin-like growth factor 1 (IGF1) are ubiquitous growth factors that regulate proliferation in most mammalian tissues including pancreatic islets. To explore the specificity of insulin receptors in compensatory beta-cell growth, we examined two models of insulin resistance. In the first model, we used li...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0608703104
更新日期:2007-05-22 00:00:00
abstract::Cigarette smoke is the major cause of lung cancer, the leading cause of cancer death, and of chronic obstructive pulmonary disease, the fourth leading cause of death in the United States. Using high-density gene expression arrays, we describe genes that are normally expressed in a subset of human airway epithelial cel...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0401422101
更新日期:2004-07-06 00:00:00
abstract::Several natural isolate E. coli strains highly resistant to sulfonamides and antibiotics are shown to contain a sulfonamide-resistant dihydropteroate synthase (2-amino-4-hydroxy-6-hydroxymethyl-7,8-dihydropteridine-diphosphate:4-aminobenzoate 2-amino-4-hydroxydihydropteridine-6-methenyltransferase, EC 2.5.1.15) in add...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.72.7.2621
更新日期:1975-07-01 00:00:00