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1.
J Environ Manage ; 352: 120038, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38232589

RESUMEN

Oil production in the Niger Delta first attained global prominence after the 1995 hangings of Ken Saro-Wiwa and eight other Ogonis. In the face of horrible publicity and credible allegations that international oil companies were complicit in systematic human rights violations against local host communities, corporate social responsibility (CSR) was embraced. CSR in the Nigerian oil industry has evolved from non-existent to limited community development programs to today's Global Memorandum of Understanding model. Yet, concomitant with CSR's growth has been a devastating increase in artisanal oil refining or "bunkering." In this article, we do not focus on industrial scale bunkering, which clearly requires high-level political support. Instead, we focus on the growth of small-scale artisanal refining in the rural Niger Delta. We situate this sector's growth in failed government and CSR policies, highlight its devastating environmental impacts, and advocate a shift away from flawed and limited CSR to legal and regulated modular refineries that, with fewer negative developmental and environmental externalities, could serve as a vital source of job creation and wealth generation.


Asunto(s)
Industrias , Minería , Pueblo de África Occidental , Niger , Políticas , Responsabilidad Social
2.
Extr Ind Soc ; 7(2): 576-579, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32322535

RESUMEN

The Niger Delta region of Nigeria is widely recognized as a complex and contentious space for oil exploration and production. Over the past few decades, the Niger Delta has witnessed large-scale mass peaceful mobilizations and rebellion-like conditions from violent militia groups. Oil companies have been implicated in violence perpetrated by Nigerian security forces. Local host communities have suffered greatly from corruption, political instability, violence and the environmental devastation of their farmlands and fishing grounds. Oil companies have increasingly turned to corporate social responsibility (CSR) initiatives to attempt to build or repair relations with oil-producing communities. There are also governmental and non-governmental humanitarian actors supporting various initiatives in the oil-producing areas. This article highlights the challenges that one long running micro-scale development project has faced due to the COVID 19 disease outbreak and the closure of all schools in Rivers State, Nigeria in March 2020. The school closures have halted some initiatives, but our weekly nutritional program has continued in new, socially distanced forms.

4.
Database (Oxford) ; 2017(1)2017 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-28365730

RESUMEN

With ever-increasing amounts of sequence data available in both the primary literature and sequence repositories, there is a bottleneck in annotating molecular function to a sequence. This article describes the biocuration process and methods used in the structure-function linkage database (SFLD) to help address some of the challenges. We discuss how the hierarchy within the SFLD allows us to infer detailed functional properties for functionally diverse enzyme superfamilies in which all members are homologous, conserve an aspect of their chemical function and have associated conserved structural features that enable the chemistry. Also presented is the Enzyme Structure-Function Ontology (ESFO), which has been designed to capture the relationships between enzyme sequence, structure and function that underlie the SFLD and is used to guide the biocuration processes within the SFLD. Database URL: http://sfld.rbvi.ucsf.edu/.


Asunto(s)
Bases de Datos de Proteínas , Enzimas/química , Enzimas/genética , Ontología de Genes , Anotación de Secuencia Molecular , Homología Estructural de Proteína , Relación Estructura-Actividad
5.
J Comput Aided Mol Des ; 20(10-11): 601-19, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17149653

RESUMEN

We report on the development and validation of a new version of DOCK. The algorithm has been rewritten in a modular format, which allows for easy implementation of new scoring functions, sampling methods and analysis tools. We validated the sampling algorithm with a test set of 114 protein-ligand complexes. Using an optimized parameter set, we are able to reproduce the crystal ligand pose to within 2 A of the crystal structure for 79% of the test cases using our rigid ligand docking algorithm with an average run time of 1 min per complex and for 72% of the test cases using our flexible ligand docking algorithm with an average run time of 5 min per complex. Finally, we perform an analysis of the docking failures in the test set and determine that the sampling algorithm is generally sufficient for the binding pose prediction problem for up to 7 rotatable bonds; i.e. 99% of the rigid ligand docking cases and 95% of the flexible ligand docking cases are sampled successfully. We point out that success rates could be improved through more advanced modeling of the receptor prior to docking and through improvement of the force field parameters, particularly for structures containing metal-based cofactors.


Asunto(s)
Diseño de Fármacos , Proteínas/química , Proteínas/metabolismo , Programas Informáticos , Algoritmos , Sitios de Unión , Simulación por Computador , Cristalografía por Rayos X , Bases de Datos de Proteínas , Enlace de Hidrógeno , Ligandos , Unión Proteica , Conformación Proteica
6.
Biochemistry ; 45(8): 2545-55, 2006 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-16489747

RESUMEN

The study of mechanistically diverse enzyme superfamilies-collections of enzymes that perform different overall reactions but share both a common fold and a distinct mechanistic step performed by key conserved residues-helps elucidate the structure-function relationships of enzymes. We have developed a resource, the structure-function linkage database (SFLD), to analyze these structure-function relationships. Unique to the SFLD is its hierarchical classification scheme based on linking the specific partial reactions (or other chemical capabilities) that are conserved at the superfamily, subgroup, and family levels with the conserved structural elements that mediate them. We present the results of analyses using the SFLD in correcting misannotations, guiding protein engineering experiments, and elucidating the function of recently solved enzyme structures from the structural genomics initiative. The SFLD is freely accessible at http://sfld.rbvi.ucsf.edu.


Asunto(s)
Bases de Datos de Proteínas , Enzimas/química , Animales , Biología Computacional , Enzimas/metabolismo , Humanos , Ingeniería de Proteínas/métodos , Relación Estructura-Actividad
7.
Pac Symp Biocomput ; : 358-69, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15759641

RESUMEN

The prediction of protein function from structure or sequence data remains a problem best addressed by leveraging information available from previously determined structure-function relationships. In the case of enzymes, the study of mechanistically diverse superfamilies can provide a rich source of structure-function information useful in functional determination and enzyme engineering. To access these relationships using a computational resource, several issues must be addressed regarding the representation of enzyme function, the organization of structure-function relationships in the superfamily context, the handling of misannotations, and reliability of classifications and evidence. We discuss here our approaches to solving these problems in the development of a Structure-Function Linkage Database (SFLD) (online at http://sfld.rbvi.ucsf.edu).


Asunto(s)
Enzimas/química , Enzimas/metabolismo , Secuencia de Aminoácidos , Catálisis , Biología Computacional/métodos , Secuencia Conservada , Enzimas/clasificación , Cinética , Ingeniería de Proteínas/métodos , Programas Informáticos , Relación Estructura-Actividad
8.
J Chem Inf Comput Sci ; 44(6): 2190-8, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15554689

RESUMEN

Integrating biological and chemical information is one key task in drug discovery, and one approach to attaining this goal is via three-dimensional pharmacophore descriptors derived from protein binding sites. The SitePrint program generates, aligns, scores, and classifies three-dimensional pharmacophore descriptors, active site grids, and ligand surfaces. The descriptors are formed from molecular fragments that have been docked, minimized, filtered, and clustered in protein active sites. The descriptors have geometric coordinates derived from the fragment positions, and they capture the shape, electrostatics, locations, and angles of entry into pockets of the recognition sites: they also provide a direct link to databases of organic molecules. The descriptors have been shown to be robust with respect to small changes in protein structure observed when multiple compounds are cocrystallized in a protein. Five aligned thrombin cocrystals with an average core alpha-carbon RMSD of 0.7 A gave three-dimensional pharmacophore descriptors with an average RMSD of 1.1 A. On a larger test set, alignment and scoring of the descriptors using clique-based alignment, and a best first search strategy with an adapted forward-looking Ullmann heuristic was able to select the global minimum three-dimensional alignment in twenty-nine out of thirty cases in less than one CPU second on a workstation. A protein family based analysis was then performed to demonstrate the usefulness of the method in producing a correlation of active site pharmacophore descriptors to protein function. Each protein in a test set of thirty was assigned membership to a family based on computed active site similarity to the following families: kinases, nuclear receptors, the aspartyl, cysteine, serine, and metallo proteases. This method of classifying proteins is complementary to approaches based on sequence or fold homology. The values within protein families for correctly assigning membership of a protein to a family ranged from 25% to 80%.


Asunto(s)
Proteínas/química , Proteínas/clasificación , Algoritmos , Sitios de Unión , Simulación por Computador , Bases de Datos Factuales
9.
Bioinformatics ; 19(15): 1997-9, 2003 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-14555634

RESUMEN

UNLABELLED: The determination of distant evolutionary relationships remains an important biological problem, and distant homologs often appear in statistically insignificant regions of sequence similarity searches. Intersect is a computer program designed to identify and visualize the overlaps between sets of sequences reported by multiple database searches. This capability extends the usefulness of database search results and aids researchers in identifying the individual sequences that best bridge sequence families and superfamilies. AVAILABILITY: The Intersect program is available from the Babbitt laboratory website at http://www.babbittlab.ucsf.edu/software/intersect


Asunto(s)
Gráficos por Computador , Bases de Datos de Proteínas , Almacenamiento y Recuperación de la Información/métodos , Alineación de Secuencia/métodos , Análisis de Secuencia de Proteína/métodos , Homología de Secuencia de Aminoácido , Programas Informáticos , Interfaz Usuario-Computador , Algoritmos , Sistemas de Administración de Bases de Datos , Evolución Molecular , Ligamiento Genético
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