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Characterizing the Function of Bilin Lyase Isomerase MpeV in Marine Synechococcus sp. RS9916
No full textCyanobacteria are prolific contributors to global primary production and are found ubiquitously around the world in both marine and freshwater environments. Synechococcus sp. RS9916 (hereafter, RS9916), a marine species of cyanobacteria, contain a membrane-bound protein complex with covalently bound bilin chromophores, called a phycobilisome (PBS), responsible for harvesting light energy and directing it into photosystem II. In RS9916, the PBS rods contain two types of phycoerythrin (PEI and PEII), the most distal phycobiliproteins (PBPs) of the complex. Enzymes known as bilin lyases catalyze attachment of bilin chromophores to these PBPs. MpeV is a putative lyase in RS9916 with homology to CpeF, a lyase from freshwater cyanobacteria Fremyella diplosiphon (Fd). MpeV is hypothesized to attach phycoerythrobilin (PEB) and simultaneously isomerize to phycourobilin (PUB) at the doubly ligated Cys-50, 61 residues on the beta subunit of PEI (CpeB). Using a heterologous expression system, recombinant MpeV was coexpressed with CpeB in E. coli, along with the genes required for PEB synthesis. Recombinant CpeB was then purified and analyzed by absorbance and fluorescence spectroscopy followed by SDS-PAGE. These samples were further analyzed by LC-MS-MS. MpeV was found to covalently attach PUB to Cys-50, 61 of CpeB. This activity increased when CpeB was partially chromophorylated by CpeS, a lyase that adds PEB to Cys-82. Additionally, there was an increase in MpeV activity when it was coexpressed with CpeZ, a homolog of a chaperone-like protein in Fd. A similar expression system was used to examine the activity of MpeV on the beta subunit of PEII (MpeB), with some PUB attachment detected at the Cys-50, 61 residues. Therefore MpeV is a lyase-isomerase for beta-phycoerythrin subunits and facilitates two thioether linkages to PUB at rings A and D to Cys-50 and Cys-61
Picturing Things
Get PDFMy creative process is a ritual I use to examine my personal narrative. Digital photography is a way for me to mine an object or environment with an obsessive emphasis, and extract an image that signifies something relatable. By employing tropes derived from my personal narrative, and filtering them through image manipulation software; I am able to dramatize aspects of perspective and scale. With an automatic mark guided by printed images and projections of digital panoramic images, the surface and resulting picture comes into focus. This is a way for me to move past my experiences. Achieving this level of intimacy with the mundane objects or environments makes it possible for me to develop a personal iconography
Summer Troubles and Other Poems
Get PDFFollowing the example of Gary Snyder\u27s Axe Handles, I introduce my poetics and poems in the preface. Other influences, including Lucille Clifton, John Ashbery, and Anne Carson, are also explored. The original poetry that follows the preface attempts to enact the language of philosophical exploration, relationships, memory, conversation, and meditation while paying close attention to the musicality of everyday speech and avoiding clear and specific conclusions
Sugarcane Crossroads
Get PDFThe following manuscript is a collection of lyric poetry that touches on themes of family history, love, and labor in the service industry. It is divided into three sections. The speaker in the work dwells in mostly private spaces and deals with private symbols such as, water, to represent the father figure in the poems
Road Closed to Thru Traffic
Get PDFThis collection of nine fiction stories explores the journeys of men and women who find themselves unable to continue on the path they\u27ve set for themselves. So often, the roads we follow are dictated by social conditioning. This collection considers how are paths are predetermined by social norms and follows the characters as they react to unexpected obstacles encountered in common scenarios. Will they forge new paths? Turn back? Or will they take a detour and return to their original road
Her Sweetest Comeback
Get PDFKelly Gangeness Le’s poetry manuscript focuses on paradoxical values concerning horror and humor paired with family and isolation. With the aesthetic approach that poetry ought to resemble the emotional intensity of music, Le strives for animated language. Her influences come from coarse, post-hardcore music and Lucie Brock-Broido’s scholarly yet brutal poetry. Thus she negotiates between lowbrow and literary dynamics. Family; Horror; Humor; Dissonanc
When I Wake
Get PDFThis paper sets out to detail the making of When I Wake with specific attention being paid to the mental processes of, the author, Summer Pierce throughout the undertaking. The paper, much like the filmmaking process, will discuss in succession the inspirations for the film, pre-production formulations, production of the film, post-production procedures, and analysis thereof
Corporate Leverage, Constraints, and Compliance
Get PDFThe first chapter evaluates the zero-leverage effect on firms\u27 financial constraints. Moreover, using investment- and cash-to-cash-flow sensitivities as financial constraint indicators, the results suggest that unleveraged firms are expected to face lower constraints relative to leveraged firms. Lastly, the results indicate that the zero-leverage effect on firms’ financial constraints is more likely stronger for smaller firms, zero-dividend firms, firms with lower proportions of tangible assets, and growth firms. The second chapter develops a new quantitative measure that reflects the extent to which a firm complies to Shariah relative to the other firms located in a certain region at a certain time. This measure can be customized to be consistent with each investor’s objectives, constraints, and beliefs. We argue that the use of this measure is preferable to the existing use of ratio thresholds for the following two reasons. First, it is more Shariah-appropriate because it provides the Shariah-compliant investor with a clear understanding of the relative compliance status of each firm he wishes to invest in. Second, it can be incorporated into any portfolio optimization model to create a balance between improving Shariah compliance and not compromising investment returns
A Transcriptomic Exploration of Hawaiian Drosophilid Development and Evolution
Get PDFOne in four known species of fruit flies inhabit the Hawaiian Islands. From a small number of colonizing flies, a wide range of species evolved, some of which managed to reverse-colonize other continental environments. In order to explore the developmental pathways, which separate the Hawaiian Drosophila proper and the Scaptomyza group that contains reverse-colonized species, the transcriptomes of two better-known species in each group, Scaptomyza anomala and Drosophila grimshawi, were analyzed to find changes in gene expression between the two groups. This study describes a novel transcriptome for S. anomala studies as well as unusual changes in gene expression in D. grimshawi relative to other species, revealing priorities of both species in early development
Detection of Whale Acoustic Signals in the Northern Gulf of Mexico LADC-GEMM Database
Get PDFLow-pass Fourier filter, wavelet filter, as well as matched filter detection methods were used to detect baleen whale signals in northern Gulf of Mexico data collected by the Littoral Acoustic Demonstration Center (LADC) consortium. Some potential low frequency signals appeared on the matched filter output figure. The shape of the signals is in line with one of the typical signal shapes of fin whales--vertical down-sweeps with 18s-time interval. Another shape of the signals is in line with one of the call type shapes of Bryde\u27s whales--down-sweeps with 7s-time interval. A high-pass Fourier filter was also used to find toothed whale high frequency sounds in the Gulf of Mexico data. The sounds featuring click trains and codas belonging to sperm whales have been clearly identified