Bioinorganic Chemistry

This book covers material that could be included in a one-quarter or one-semester course in bioinorganic chemistry for graduate students and advanced undergraduate students in chemistry or biochemistry. We believe that such a course should provide students with the background required to follow the research literature in the field. The topics were chosen to represent those areas of bioinorganic chemistry that are mature enough for textbook presentation. Although each chapter presents material at a more advanced level than that of bioinorganic textbooks published previously, the chapters are not specialized review articles. What we have attempted to do in each chapter is to teach the underlying principles of bioinorganic chemistry as well as outlining the state of knowledge in selected areas. We have chosen not to include abbreviated summaries of the inorganic chemistry, biochemistry, and spectroscopy that students may need as background in order to master the material presented. We instead assume that the instructor using this book will assign reading from relevant sources that is appropriate to the background of the students taking the course. For the convenience of the instructors, students, and other readers of this book, we have included an appendix that lists references to reviews of the research literature that we have found to be particularly useful in our courses on bioinorganic chemistry

An Examination of the Reading First Program at a Southeastern Virginia Elementary School and the Impact on K–2 Student Reading Achievement

Reading First was a federal initiative aimed at improving reading instruction and implementing programs and strategies grounded in scientifically-based reading research. The legislation was predicated on research findings that high-quality reading instruction and intervention in the primary grades significantly reduces the numbers of students who experience difficulties in later grades. This study examined the Reading First program at an elementary school in southeastern Virginia from 2006-2008. Specifically, the researcher investigated the impact of the independent variable, the tier three model of intervention on K-2 student reading achievement. Quantitative data was garnered from 792 K-2 student participants attending the research site. Using a regression discontinuity design, the study evaluated the significance of the multi-tiered intervention model on student reading achievement using a pre-test/post-test program group strategy (Trochin, 1982; Stanley, 1991; Shadish, Cook, & Campbell, 2002). The Phonological Awareness Literacy Screenings (PALS), K PALS and PALS 1-3, served as the study\u27s dependent measures examining differences in pre-post student scores to determine statistical significance in literacy growth among the population sample (Invernizzi, Meier, & Juel, 2003). Using PALS benchmark ranges established by the local division, 2006-2008 K-2 students were identified as tier 1, meeting benchmark standards, tier 2, strategic, or tier 3, intensive. The researcher evaluated the mean differences between groups using an Analysis of Variance (ANOVA). Additional independent variables analyzed included pre-k experience, student tier classification, grade level, and year. Statistical significance existed between pre-test/post-test scores among the 2006-2007 and 2007-2008 tier 1 student subgroups in Grade 1. No significant relationship was found among year 1 or year 2 tier 1 student subgroups in Kindergarten or Grade 2. Results of one-way analyses of variance showed statistical significance between pre-test/post-test scores among tier 2 student subgroups in Kindergarten, Grade 1, and Grade 2. Statistical significance existed between pre-test/post-test scores among the 2006-2007 and 2007-2008 tier 3 student subgroups in Kindergarten. No significant relationship was found among year 1 or year 2 tier 3 student subgroups in Grade 1 or Grade 2

Building Inequality: A Case Study of White, Black, and Latino Contractors in the Atlanta Construction Industry

In this exploratory case study, I compare and contrast the self-employment experiences and hiring practices of Black, Latino, and White business owners in the Atlanta construction industry. While much of the ethnic entrepreneurship literature has explained the racialized differences between racial and ethnic groups concerning self-employment and their hiring practices, few studies have been able to provide a clear explanation of the mechanisms racial groups use to maintain an economic and social edge without being overtly racist. Furthermore, many scholars have not yet begun to compare the experiences of Whites, Blacks, and Latinos in the South and how their racial ideologies and competition spur on discrimination and racism in a supposedly “color-blind” environment. To address these gaps, I interviewed 42 White, Black, and Latino sub- and general contractors in the Atlanta metropolitan area. I also collected observational data by visiting the worksites of my respondents and attending organizational meetings. Results suggest that even though many of my respondents indicated that racial dissimilarities were due to individual effort and poor motivation, I find that these color-blind ideologies work well to solidify the racial hierarchy and privilege White contractors. I also find that these ideologies block Blacks and Latinos from obtaining better financing, building a good reputation, or having access to important social connections that introduced most contractors to more lucrative prospects. More importantly, the White “good ole’ boy” networks worked as a mechanism to exclude Blacks and Latinos from more lucrative connections, and keep any interactions to a strictly employee-employer relationship. However, these business owners’ hiring practices are the same: they want the cheapest and hardest-working employees they can get, who are usually Latino laborers. By moving beyond the black/white dichotomy, this study offers new explanations of race relations and racial inequality in a metropolitan area recently affected by immigration. Finally, I show that competition pushes these contractors to be more discriminatory, especially when Latino immigrants threaten their hard-earned social positions. My empirical and conceptual analyses provide a good start toward explaining how racism and discrimination is organized and continues to persist in a major U.S. industry

Synthesis, Characterization, and Oxygenation Studies of Carboxylate-Bridged Diiron(II) Complexes with Aromatic Substrates Tethered to Pyridine Ligands and the Formation of a Unique Trinuclear Complex

In this study, diiron(II) complexes were synthesized as small molecule mimics of the reduced active sites in the hydroxylase components of bacterial multicomponent monooxygenases (BMMs). Tethered aromatic substrates were introduced in the form of 2-phenoxypyridines, incorporating hydroxy and methoxy functionalities into windmill-type diiron(II) compounds [Fe[subscript 2](μ-O[subscript 2]CAr[superscript R])[subscript 2](O[subscript 2]CAr[superscript R])[subscript 2](L)[subscript 2]] (1–4), where[superscript –]O[subscript 2]CAr[superscript R] is a sterically encumbering carboxylate, 2,6-bis(4-fluorophenyl)-, or 2,6-bis(p-tolyl)benzoate (R = 4-FPh or Tol, respectively). The inability of 1–4 to hydroxylate the aromatic substrates was ascertained. Upon reaction with dioxygen, compounds 2 and 3 (L = 2-(m-MeOPhO)Py, 2-(p-MeOPhO)Py, respectively) decompose by a known bimolecular pathway to form mixed-valent diiron(II,III) species at low temperature. Use of 2-(pyridin-2-yloxy)phenol as the ligand L resulted in a doubly bridged diiron complex 4 and an unprecedented phenoxide-bridged triiron(II) complex 5 under slightly modified reaction conditions.National Institute of General Medical Sciences (U.S.) (Grant GM032134

Redox activation of metal-based prodrugs as a strategy for drug delivery

This review provides an overview of metal-based anticancer drugs and drug candidates. In particular, we focus on metal complexes that can be activated in the reducing environment of cancer cells, thus serving as prodrugs. There are many reports of Pt and Ru complexes as redox-activatable drug candidates, but other d-block elements with variable oxidation states have a similar potential to serve as prodrugs in this manner. In this context are compounds based on Fe, Co, or Cu chemistry, which are also covered. A trend in the field of medicinal inorganic chemistry has been toward molecularly targeted, metal-based drugs obtained by functionalizing complexes with biologically active ligands. Another recent activity is the use of nanomaterials for drug delivery, exploiting passive targeting of tumors with nano-sized constructs made from Au, Fe, carbon, or organic polymers. Although complexes of all of the above mentioned metals will be described, this review focuses primarily on Pt compounds, including constructs containing nanomaterials.German Academic Exchange Service (DAAD fellowship)German Academic Exchange Service (DAAD reintegration grant)National Cancer Institute (U.S.) (grant CA034992

Imaging mobile zinc in biology

Trafficking and regulation of mobile zinc pools influence cellular functions and pathological conditions in multiple organs, including brain, pancreas, and prostate. The quest for a dynamic description of zinc distribution and mobilization in live cells fuels the development of increasingly sophisticated probes. Detection systems that respond to zinc binding with changes of their fluorescence emission properties have provided sensitive tools for mobile zinc imaging, and fluorescence microscopy experiments have afforded depictions of zinc distribution within live cells and tissues. Both small-molecule and protein-based fluorescent probes can address complex imaging challenges, such as analyte quantification, site-specific sensor localization, and real-time detection.National Institute of General Medical Sciences (U.S.) (grant GM065519

19F NMR study of ligand dynamics in carboxylate-bridged diiron(II) complexes supported by a macrocyclic ligand

A series of asymmetrically carboxylate-bridged diiron(II) complexes featuring fluorine atoms as NMR spectroscopic probes, [Fe[subscript 2](PIM)(Ar[superscript 4F-Ph]CO[subscript 2])[subscript 2]] (10), [Fe[subscript 2](F[subscript 2]PIM)(Ar[superscript Tol]CO[subscript 2])[subscript 2]] (11), and [Fe[subscript 2](F[subscript 2]PIM)(Ar[superscript 4F-Ph]CO[subscript 2])[superscript 2]] (12), were prepared and characterized by X-ray crystallography, Mössbauer spectroscopy, and VT [superscript19]F NMR spectroscopy. These complexes are part of a rare family of syn-N diiron(II) complexes, [Fe[subscript 2](X[subscript 2]PIM)(RCO[subscript 2])[superscript 2]], that are structurally very similar to the active site of the hydroxylase enzyme component of reduced methane monooxygenase (MMOH[subscript red]). Solution characterization of these complexes demonstrates that they undergo intramolecular carboxylate rearrangements, or carboxylate shifts, a dynamic feature relevant to the reactivity of the diiron centers in bacterial multicomponent monooxygenasesNational Institute of General Medical Sciences (U.S.) (Grant GM 32114)National Science Foundation (U.S.). Graduate Research Fellowship Program (Grant 1122374