Abstract：
:Recent advances in metabolic engineering have demonstrated that microbial biosynthesis can provide a viable alternative to chemical synthesis for the production of bulk and fine chemicals. Introduction of a new biosynthetic pathway typically requires the expression of multiple heterologous enzymes in the production host, which can impose stress on the host cell and, thereby, limit performance of the pathway. Unfortunately, analysis and treatment of the host stress response can be difficult, because there are many sources of stress that may interact in complex ways. We use a systems biological approach to analyze the stress imposed by expressing different enzyme variants from a lineage of soluble P450 monooxygenases, previously evolved for heterologous activity in Saccharomyces cerevisiae. Our analysis identifies patterns of stress imposed on the host by heterologous enzyme overexpression that are consistent across the evolutionary lineage, ultimately implicating heme depletion as the major stress. We show that the monooxygenase evolution, starting from conditions of either high or low stress, caused the cellular stress to converge to a common level. Overexpression of rate-limiting enzymes in the endogenous heme biosynthetic pathway alleviates the stress imposed by expression of the P450 monooxygenases and increases the enzymatic activity of the final evolved P450 by an additional 2.3-fold. Heme overexpression also increases the total activity of an endogenous cytosolic heme-containing catalase but not a heterologous P450 that is membrane-associated. This work demonstrates the utility of combining systems and synthetic biology to analyze and optimize heterologous enzyme expression.
journal_name
Proc Natl Acad Sci U S Aauthors
Michener JK,Nielsen J,Smolke CDdoi
10.1073/pnas.1212287109subject
Has Abstractpub_date
2012-11-20 00:00:00pages
19504-9issue
47eissn
0027-8424issn
1091-6490pii
1212287109journal_volume
109pub_type
杂志文章abstract：:An unsaturated fatty acid-requiring mutant derived from Chinese hamster ovary (CHO) cells has been isolated and characterized. This mutant grows normally when oleate or other unsaturated fatty acids are supplemented in the growth medium. Unlike the wild-type CHO cells, growth stops when medium is deprived of unsaturat...
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.73.1.24
更新日期：1976-01-01 00:00:00
abstract：:The Ca(2+)-binding protein calbindin D28k (CB) is vital for the normal function of the central nervous system but its specific functional role is largely unclear. CB is typically described as a mobile Ca(2+)buffer that shapes the spatiotemporal extent of cellular Ca(2+)signals. Recent biochemical data, however, indica...
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.0407855102
更新日期：2005-04-19 00:00:00
abstract：:We present a 3D topological picture-language for quantum information. Our approach combines charged excitations carried by strings, with topological properties that arise from embedding the strings in the interior of a 3D manifold with boundary. A quon is a composite that acts as a particle. Specifically, a quon is 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.1621345114
更新日期：2017-03-07 00:00:00
abstract：:Rapid electrical conduction in the His-Purkinje system tightly controls spatiotemporal activation of the ventricles. Although recent work has shed much light on the regulation of early specification and morphogenesis of the His-Purkinje system, less is known about how transcriptional regulation establishes impulse con...
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.1106911108
更新日期：2011-08-16 00:00:00
abstract：:Electron collisions with atoms, ions, molecules, and surfaces are critically important to the understanding and modeling of low-temperature plasmas (LTPs), and so in the development of technologies based on LTPs. Recent progress in obtaining experimental benchmark data and the development of highly sophisticated compu...
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.1606132113
更新日期：2016-06-28 00:00:00
abstract：:Experiments were designed to determine the interrelationship between cyclic AMP and Ca(2+) during the processes of sperm capacitation and the acrosome reaction. In minimal culture media containing pyruvate and lactate as substrates, guinea pig spermatozoa required a minimum of 1.0-1.5 hr to capacitate in the presence ...
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.76.11.5699
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abstract：:An important goal in biology is to predict from sequence data the high-resolution structures of proteins and the interactions that occur between them. In this paper, we describe a computational approach that can make these types of predictions for a series of coiled-coil dimers. Our method comprises a dual strategy th...
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.261563398
更新日期：2001-12-18 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.87.13.4991
更新日期：1990-07-01 00:00:00
abstract：:We present a method for studying multiple retroviral integration events into a small DNA target in vivo. Episomal simian virus 40 (SV40) genomes established by infection of CV-1 cells served as integration targets during subsequent infection with murine leukemia virus (MLV). Using a PCR-based assay for the abundance 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.89.19.9237
更新日期：1992-10-01 00:00:00
abstract：:Gyrate atrophy of the choroid and retina (GA) is an inherited chorioretinal degeneration caused by deficiency of ornithine delta-aminotransferase (OAT; L-ornithine: 2-oxo-acid aminotransferase; EC 2.6.1.13). GA is one of the "Finnish genetic diseases," a group of several rare monogenic disorders that occur with increa...
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.86.1.197
更新日期：1989-01-01 00:00:00
abstract：:The tips of the digits of some mammals, including human infants and mice, are capable of complete regeneration after injury. This process is reliant on the presence of the overlaying nail organ and is mediated by a proliferative blastema. Epithelial Wnt/β-catenin signaling has been shown to be necessary for mouse digi...
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.1518874112
更新日期：2015-10-27 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.62.2.415
更新日期：1969-02-01 00:00:00
abstract：:Transcription factor TFIID consists of TATA binding protein (TBP) and at least eight TBP-associated factors (TAFs). As TAFs are required for activated but not basal transcription, we have proposed that TAFs act as coactivators to mediate signals between activators and the basal transcription machinery. Here we report ...
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.92.13.5788
更新日期：1995-06-20 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.0503965102
更新日期：2005-06-28 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.0712392105
更新日期：2008-03-11 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.70.10.2993
更新日期：1973-10-01 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.1218887109
更新日期：2012-12-11 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
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更新日期：2007-04-03 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
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journal_title：Proceedings of the National Academy of Sciences of the United States of America
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更新日期：1994-07-05 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
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更新日期：1989-01-01 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.1608587113
更新日期：2016-11-22 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.0606129103
更新日期：2006-10-24 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.94.25.13932
更新日期：1997-12-09 00:00:00
abstract：:Precise genome editing is a valuable tool to study gene function in model organisms. Prime editing, a precise editing system developed in mammalian cells, does not require double-strand breaks or donor DNA and has low off-target effects. Here, we applied prime editing for the model organism Drosophila melanogaster and...
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.2021996118
更新日期：2021-01-05 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.0806173105
更新日期：2008-11-04 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.85.10.3657
更新日期：1988-05-01 00:00:00
abstract：:The in situ stimulation of Fe(III) oxide reduction by Geobacter bacteria leads to the concomitant precipitation of hexavalent uranium [U(VI)] from groundwater. Despite its promise for the bioremediation of uranium contaminants, the biological mechanism behind this reaction remains elusive. Because Fe(III) oxide reduct...
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.1108616108
更新日期：2011-09-13 00:00:00
abstract：:Proteopithecus sylviae is an archaic anthropoid from the late Eocene quarry L-41, Fayum Province, Egypt. The dentition of Proteopithecus is very primitive and does not closely resemble that of other, better known, primates from the Fayum (e.g., parapithecids and propliopithecids). The dental morphology, much of which ...
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.94.25.13760
更新日期：1997-12-09 00:00:00
abstract：:Targeted drug delivery critically depends on the binding selectivity of cargo-transporting colloidal particles. Extensive theoretical work has shown that two factors are necessary to achieve high selectivity for a threshold receptor density: multivalency and weak interactions. Here, we study a model system of DNA-coat...
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.2003968117
更新日期：2020-09-15 00:00:00
