James Wachira

Dr. James Wachira

Biology, Morgan State University, Baltimore, Maryland, USA
orcid

Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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6 August 2018 in BMC Genomics
Verified
Journal Article
Open access
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HYHengfu Yin
Hengfu Yin
HGHao-Bo Guo
Hao-Bo Guo
DWDavid J. Weston
David J. Weston
ABAnne M. Borland
Anne M. Borland
PRPriya Ranjan
Priya Ranjan
Xiaohan YangXiaohan Yang
Xiaohan Yang
Crassulacean acid metabolism (CAM) enhances plant water-use efficiency through an inverse day/night pattern of stomatal closure/opening that facilitates nocturnal CO2 uptake. CAM has evolved independently in over 35 plant lineages, accounting for ~ 6% of all higher plants. Agave species are highly heat- and drought-tolerant, and have been domesticated as model CAM crops for beverage, fiber, and biofuel production in semi-arid and arid regions. However, the genomic basis of evolutionary innovation of CAM in genus Agave is largely unknown. Using an approach that integrated genomics, gene co-expression networks, comparative genomics and protein structure analyses, we investigated the molecular evolution of CAM as exemplified in Agave. Comparative genomics analyses among C3, C4 and CAM species revealed that core metabolic components required for CAM have ancient genomic origins traceable to non-vascular plants while regulatory proteins required for diel re-programming of metabolism have a more recent origin shared among C3, C4 and CAM species. We showed that accelerated evolution of key functional domains in proteins responsible for primary metabolism and signaling, together with a diel re-programming of the transcription of genes involved in carbon fixation, carbohydrate processing, redox homeostasis, and circadian control is required for the evolution of CAM in Agave. Furthermore, we highlighted the potential candidates contributing to the adaptation of CAM functional modules. This work provides evidence of adaptive evolution of CAM related pathways. We showed that the core metabolic components required for CAM are shared by non-vascular plants, but regulatory proteins involved in re-reprogramming of carbon fixation and metabolite transportation appeared more recently. We propose that the accelerated evolution of key proteins together with a diel re-programming of gene expression were required for CAM evolution from C3 ancestors in Agave.

2 June 2025 in Applied Biosciences
Verified
Journal Article
Open access
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Maruf Olaide YekeenMaruf Olaide Yekeen
Maruf Olaide Yekeen
MIMubarak Ibrahim
Mubarak Ibrahim
JWJames Wachira
James Wachira
SPSaroj K Pramanik
Saroj K Pramanik
An aqueous leaf extract of Egeria densa was used to green-synthesize iron (II) and iron (III) oxide nanoparticles from ferrous sulphate and ferric chloride, respectively. The successful green synthesis of the nanoparticles was confirmed through UV–visible spectroscopy, and the colour of the mixtures changed from light-yellow to green-black and reddish-brown for FeO–NPs and Fe2O3–NPs, respectively. The morphological characteristics of the nanoparticles were determined using an X-ray diffractometer (XRD), a Fourier transform infrared spectrophotometer (FTIR), a transmission electron microscope (TEM), and energy-dispersive X-ray spectroscopy (EDX). The UV–Vis spectrum of the FeO–NPs showed a sharp peak at 290 nm due to the surface plasmon resonance, while that of the Fe2O3–NPs showed a sharp peak at 300 nm. TEM analysis revealed that the FeO–NPs were oval to hexagonal in shape and were clustered together with an average size of 18.49 nm, while the Fe2O3-NPs were also oval to hexagonal in shape, but some were irregularly shaped, and they clustered together with an average size of 27.96 nm. EDX analysis showed the presence of elemental iron and oxygen in both types of nanoparticles, indicating that these nanoparticles were essentially present in oxide form. The XRD patterns of both the FeO–NPs and Fe2O3–NPs depicted that the nanoparticles produced were crystalline in nature and exhibited the rhombohedral crystal structure of hematite. The FT-IR spectra revealed that phenolic compounds were present on the surface of the nanoparticles and were responsible for reducing the iron salts into FeO–NPs and Fe2O3–NPs. Conclusively, this work demonstrated for the first time the ability of Elodea aqueous extract to synthesize iron-based nanoparticles from both iron (II) and iron (III) salts, highlighting its versatility as a green reducing and stabilizing agent. The dual-path synthesis approach provides new insights into the influence of the precursor oxidation state on nanoparticle formation, thereby expanding our understanding of plant-mediated nanoparticle production and offering a sustainable route for the fabrication of diverse iron oxide nanostructures. Furthermore, it provides a simple, cost-effective, and environmentally friendly method for the synthesis of the FeO–NPs and Fe2O3–NPs using Egeria densa.

23 September 2024 in Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy
Verified
Journal Article
Open access
SUSisay Uota
Sisay Uota
BHBor-Jang Hwang
Bor-Jang Hwang
RBRay Butcher
Ray Butcher
RMRoger Mullins
Roger Mullins
JWJames Wachira
James Wachira
FAFasil Abebe
Fasil Abebe
A new sensor based on Ethylbenzothiazolium-2-hydroxynaphthaldehyde conjugate-based fluorescent sensor, (E)-3-ethyl-2-(2-(2-hydroxynaphthalen-1-yl) vinyl) benzo[d]thiazol-3-ium iodide (SU-1) was designed and synthesized. The structure of SU-1 was confirmed by 1H NMR, 13C NMR, HRMS, and single crystal XRD spectral analysis. SU-1 displayed a colorimetric and fluorometric response in a DMSO:H2O (1:1,v/v) matrix, changing color from pale yellow to colorless visible to the naked eye, accompanied by a ∼ 120 nm red-shift in the absorption spectra upon CN- addition. This shift, due to formation of deprotonation followed by the nucleophilic attack on the benzothiazolium ring's double bond, disrupts π-conjugation, blocking intramolecular charge transfer within SU-1. However, competitive anions showed negligible interference while detecting CN-. The Limit of detection for CN- was determined to be 0.27 nM, significantly below the WHO's permissible CN- concentration in drinking water (1.9 μM). Job's plot analysis shows that the binding stoichiometry of SU-1 to CN- is a 1:1, with a stability constant (Ka) of 1.58 x 104 M-1. The sensor demonstrated practical applications in environmental water samples and fluorescence imaging of intracellular CN- in CAD cell line.

Paul B TchounwouPaul B Tchounwou
Paul B Tchounwou
MMMohamad Malouhi
Mohamad Malouhi
Elizabeth O. OfiliElizabeth O. Ofili
Elizabeth O. Ofili
Emma FernandezEmma Fernandez
Emma Fernandez
Daniel F. SarpongDaniel F. Sarpong
Daniel F. Sarpong
Yanyuan WuYanyuan Wu
Yanyuan Wu
Funded by the National Institutes of Health (NIH), the Research Centers in Minority Institutions (RCMI) Program fosters the development and implementation of innovative research aimed at improving minority health and reducing or eliminating health disparities. Currently, there are 21 RCMI Specialized (U54) Centers that share the same framework, comprising four required core components, namely the Administrative, Research Infrastructure, Investigator Development, and Community Engagement Cores. The Research Infrastructure Core (RIC) is fundamentally important for biomedical and health disparities research as a critical function domain. This paper aims to assess the research resources and services provided and evaluate the best practices in research resources management and networking across the RCMI Consortium. We conducted a REDCap-based survey and collected responses from 57 RIC Directors and Co-Directors from 98 core leaders. Our findings indicated that the RIC facilities across the 21 RCMI Centers provide access to major research equipment and are managed by experienced faculty and staff who provide expert consultative and technical services. However, several impediments to RIC facilities operation and management have been identified, and these are currently being addressed through implementation of cost-effective strategies and best practices of laboratory management and operation.

27 December 2024 in Inorganics
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Journal Article
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OAOyedoyin Aduroja
Oyedoyin Aduroja
RSRoosevelt Shaw
Roosevelt Shaw
SUSiasy Tesema Uota
Siasy Tesema Uota
IAIsaac Abiye
Isaac Abiye
JWJames Wachira
James Wachira
FAFasil Abebe
Fasil Abebe
A novel rhodamine-6G derivative RdN was synthesized by condensing rhodamine glyoxal and 3-hydroxy-2-naphthoic hydrazide using a microwave irradiation-assisted reaction. Colorimetric and photophysical studies have demonstrated that the molecule produced can selectively sense Pb2+ and Cu2+ ions in a solution of CH3CN/H2O (9:1, v/v). The spirolactam ring of RdN opens upon complexation with the cations, forming a highly fluorescent complex and a visible color change in the solution. The compound RdN was further studied with the help of computational methods such as the Density Functional Theory (DFT) method and time-dependent density theory (TD-DFT) calculations to study the binding interactions and properties of the molecule. DFT calculations and job plot data supported the 2:1 complex formation between RdN and Pb2+/Cu2+. The limit of detection for Pb2+ was determined to be 0.112 µM and 0.130 µM for Cu2+. The probe RdN was applied to the image of Pb2+ and Cu2+ ions in living cells and is safe for biomedical applications. It is used to monitor Pb2+ in environmental water samples.

7 August 2020 in Critical Studies in Media Communication
Verified
Journal Article
Closed access
JWJames Wachira
James Wachira
Wangari Maathai’s environmental activism aims at the restoration of ecosystems to guarantee ecological sustainability. It is a mission premised on the need to place measures such as the planting of trees to remedy environmental wounds. To stress both the gravity of loss and the possibilities of arresting it, the metaphor of healing the earth underlines her vision that speaks to concerns of Afrofuturism. However, scholarly attention to ways activism finds expression in Afrofuturistic discourses needs to increase. Therefore, this study zooms in on and analyzes notions of remediation in Wanuri Kahiu’s short film Pumzi (2009). The discussion of the film teases out and aims to mobilize the content of Wangari Maathai’s Nobel Lecture of 2004. The film blends traits of science fiction with aspects of Gĩkũyũ orature to position Pumzi as nurturing Afrofuturist environmental imaginary that builds on Wangari Maathai’s call to heal the earth.