Assessing the Potential Content of Ethyl Carbamate in White, Red, and Rosé Wines as a Key Factor for Pursuing Urea Degradation by Purified Acid Urease

ABSTRACT Urease, a nickel-containing metalloenzyme, was the first enzyme to be crystallized and has a prominent position in the history of biochemistry. In the present study, we identified a nickel urease gene cluster, ureABCEFGDH, in Bacillus paralicheniformis ATCC 9945a and characterized it in Escherichia coli. Enzymatic assays demonstrate that this oxygen-stable urease is also an iron-containing acid urease. Heterologous expression assays of UreH suggest that this accessory protein is involved in the transmembrane transportation of nickel and iron ions. Moreover, this iron-containing acid urease has a potential application in the degradation of urea in rice wine. The present study not only enhances our understanding of the mechanism of activation of urease but also provides insight into the evolution of metalloenzymes. IMPORTANCE An iron-containing, oxygen-stable acid urease from B. paralicheniformis ATCC 9945a with good enzymatic properties was characterized. This acid urease shows activities toward both urea and ethyl carbamate. After digestion with 6 U/ml urease, approximately 92% of the urea in rice wine was removed, suggesting that this urease has great potential in the food industry.

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Attachment of oral bacteria to titanium surfaces: An SEM study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170074 ◽

1994 ◽

Vol 52 ◽

pp. 468-469

Author(s):

J. E. Laffoon ◽

R. L. Anderson ◽

J. C. Keller ◽

C. D. Wu-Yuan

Keyword(s):

Technical Problem ◽

Titanium Implant ◽

Oral Bacteria ◽

Bacterial Cells ◽

Thin Sections ◽

Surface Ultrastructure ◽

Sem Study ◽

Key Factor ◽

Titanium Surfaces

Titanium (Ti) dental implants have been used widely for many years. Long term implant failures are related, in part, to the development of peri-implantitis frequently associated with bacteria. Bacterial adherence and colonization have been considered a key factor in the pathogenesis of many biomaterial based infections. Without the initial attachment of oral bacteria to Ti-implant surfaces, subsequent polymicrobial accumulation and colonization leading to peri-implant disease cannot occur. The overall goal of this study is to examine the implant-oral bacterial interfaces and gain a greater understanding of their attachment characteristics and mechanisms. Since the detailed cell surface ultrastructure involved in attachment is only discernible at the electron microscopy level, the study is complicated by the technical problem of obtaining titanium implant and attached bacterial cells in the same ultra-thin sections. In this study, a technique was developed to facilitate the study of Ti implant-bacteria interface.Discs of polymerized Spurr’s resin (12 mm x 5 mm) were formed to a thickness of approximately 3 mm using an EM block holder (Fig. 1). Titanium was then deposited by vacuum deposition to a film thickness of 300Å (Fig. 2).

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Forum: Morphological Awareness as a Key Factor in Language-Literacy Success for Academic Achievement

Language Speech and Hearing Services in Schools ◽

10.1044/2020_lshss-20-00064 ◽

2020 ◽

Vol 51 (3) ◽

pp. 509-513

Author(s):

Ashley Bourque Meaux ◽

Julie A. Wolter ◽

Ginger G. Collins

Keyword(s):

Academic Achievement ◽

Academic Success ◽

Literacy Development ◽

Morphological Awareness ◽

Language And Literacy ◽

Speech Language Pathologists ◽

School Based ◽

Literacy Success ◽

Key Factor ◽

Language And Literacy Development

Purpose This article introduces the Language, Speech, and Hearing Services in Schools Forum: Morphological Awareness as a Key Factor in Language-Literacy Success for Academic Achievement. The goal of this forum is to relate the influence morphological awareness (MA) has on overall language and literacy development with morphology acting as the “binding agent” between orthography, phonology, and semantics ( Perfetti, 2007 ) in assessment and intervention for school-aged children. Method This introduction provides a foundation for MA development and explores the influence MA has over the course of school-aged language and literacy development. Through summaries of the 11 articles in this forum, school-based speech-language pathologists will be able to convey the importance of MA to promote successful educational outcomes for kindergarten to adolescent students. The forum explores researcher-developed assessments used to help identify MA skill level in first- through eighth-grade students at risk for literacy failure to support instructional needs. The forum also provides school-based speech-language pathologists with details to design and implement MA interventions to support academic success for school-aged students with varying speech-language needs (e.g., dual language emersion, vocabulary development, reading comprehension) using various service delivery models (e.g., small group, classroom-based, intensive summer camps). Conclusion MA is effective in facilitating language and literacy development and as such can be an ideally focused on using multilinguistic approaches for assessment and intervention. The articles in this issue highlight the importance in assessment measures and intervention approaches that focus on students' MA to improve overall academic success in children of all ages and abilities.

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