Severity: Warning
Message: fopen(/var/lib/php/sessions/ci_session39l5qrn0m5r9507tc8vevctrvporqn89): Failed to open stream: No space left on device
Filename: drivers/Session_files_driver.php
Line Number: 177
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File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: session_start(): Failed to read session data: user (path: /var/lib/php/sessions)
Filename: Session/Session.php
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File: /var/www/html/index.php
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Function: require_once
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Message: Undefined array key "choices"
Filename: controllers/Detail.php
Line Number: 249
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 249
Function: _error_handler
File: /var/www/html/index.php
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Function: require_once
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Message: Trying to access array offset on value of type null
Filename: controllers/Detail.php
Line Number: 249
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File: /var/www/html/application/controllers/Detail.php
Line: 249
Function: _error_handler
File: /var/www/html/index.php
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Function: require_once
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Message: Trying to access array offset on value of type null
Filename: controllers/Detail.php
Line Number: 249
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 249
Function: _error_handler
File: /var/www/html/index.php
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Function: require_once
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Message: Trying to access array offset on value of type null
Filename: controllers/Detail.php
Line Number: 249
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 249
Function: _error_handler
File: /var/www/html/index.php
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Function: require_once
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Message: strpos(): Passing null to parameter #1 ($haystack) of type string is deprecated
Filename: models/Detail_model.php
Line Number: 71
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File: /var/www/html/application/models/Detail_model.php
Line: 71
Function: strpos
File: /var/www/html/application/controllers/Detail.php
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Function: insertAPISummary
File: /var/www/html/index.php
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Function: require_once
Severity: 8192
Message: str_replace(): Passing null to parameter #3 ($subject) of type array|string is deprecated
Filename: helpers/my_audit_helper.php
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File: /var/www/html/application/helpers/my_audit_helper.php
Line: 8919
Function: str_replace
File: /var/www/html/application/controllers/Detail.php
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Function: formatAIDetailSummary
File: /var/www/html/index.php
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Function: require_once
Severity: Warning
Message: Undefined array key "choices"
Filename: controllers/Detail.php
Line Number: 256
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 256
Function: _error_handler
File: /var/www/html/index.php
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Function: require_once
Severity: Warning
Message: Trying to access array offset on value of type null
Filename: controllers/Detail.php
Line Number: 256
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 256
Function: _error_handler
File: /var/www/html/index.php
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Function: require_once
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Message: Trying to access array offset on value of type null
Filename: controllers/Detail.php
Line Number: 256
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File: /var/www/html/application/controllers/Detail.php
Line: 256
Function: _error_handler
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Undefined array key "usage"
Filename: controllers/Detail.php
Line Number: 257
Backtrace:
File: /var/www/html/application/controllers/Detail.php
Line: 257
Function: _error_handler
File: /var/www/html/index.php
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Function: require_once
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Message: Trying to access array offset on value of type null
Filename: controllers/Detail.php
Line Number: 257
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File: /var/www/html/application/controllers/Detail.php
Line: 257
Function: _error_handler
File: /var/www/html/index.php
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Function: require_once
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Message: Undefined array key "usage"
Filename: controllers/Detail.php
Line Number: 258
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File: /var/www/html/application/controllers/Detail.php
Line: 258
Function: _error_handler
File: /var/www/html/index.php
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Filename: controllers/Detail.php
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Function: _error_handler
File: /var/www/html/index.php
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Message: Undefined array key "usage"
Filename: controllers/Detail.php
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Function: _error_handler
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Filename: controllers/Detail.php
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Message: Undefined array key "usage"
Filename: controllers/Detail.php
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Function: _error_handler
File: /var/www/html/index.php
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Filename: controllers/Detail.php
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File: /var/www/html/application/controllers/Detail.php
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Function: _error_handler
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Filename: controllers/Detail.php
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File: /var/www/html/application/controllers/Detail.php
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Function: _error_handler
File: /var/www/html/index.php
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Function: require_once
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Message: file_get_contents(https://...@gmail.com&api_key=61f08fa0b96a73de8c900d749fcb997acc09): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests
Filename: helpers/my_audit_helper.php
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File: /var/www/html/application/helpers/my_audit_helper.php
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Function: file_get_contents
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Function: GetPubMedArticleOutput_2016
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Function: pubMedGetRelatedKeyword
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Function: require_once
Flavoproteins often stabilize their flavin coenzyme by stacking interactions involving the isoalloxazine moiety of the flavin and an aromatic residue from the apoprotein. The bacterial FAD and folate-dependent tRNA methyltransferase TrmFO has the unique property of stabilizing its FAD coenzyme by an unusual H-bond-assisted π-π stacking interaction, involving a conserved tyrosine (Y346 in Bacillus subtilis TrmFO, BsTrmFO), the isoalloxazine of FAD and the backbone of a catalytic cysteine (C53). Here, the interaction between FAD and Y346 has been investigated by measuring the photoinduced flavin dynamics of BsTrmFO in the wild-type (WT) protein, C53A and several Y346 mutants by ultrafast transient absorption spectroscopy. In C53A, the excited FAD very rapidly (0.43 ps) abstracts an electron from Y346, yielding the FAD˙-/Y346OH˙+ radical pair, while relaxation of the local environment (1.3 ps) of the excited flavin produces a slight Stokes shift of its stimulated emission band. The radical pair then decays via charge recombination, mostly in 3-4 ps, without any deprotonation of the Y346OH˙+ radical. Presumably, the H-bond between Y346 and the amide group of C53 increases the pKa of Y346OH˙+ and slows down its deprotonation. The dynamics of WT BsTrmFO shows additional slow decay components (43 and 700 ps), absent in the C53A mutant, assigned to excited FADox populations not undergoing fast photoreduction. Their presence is likely due to a more flexible structure of the WT protein, favored by the presence of C53. Interestingly, mutations of Y346 canceling its electron donating character lead to multiple slower quenching channels in the ps-ns regime. These channels are proposed to be due to electron abstraction either (i) from the adenine moiety of FAD, a distribution of the isoalloxazine-adenine distance in the absence of Y346 explaining the multiexponential decay, or (ii) from the W286 residue, possibly accounting for one of the decays. This work supports the idea that H-bond-assisted π-π stacking controls TrmFO's active site dynamics, required for competent orientation of the reactive centers during catalysis.
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Source |
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http://dx.doi.org/10.1039/c8cp06072j | DOI Listing |
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