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Addison, H.

Publications and source records attributed to Addison, H..

2 recordsLinked to original sources

Microbial load on hair tools of tertiary-level students in Ghana: A case study of the University of Science and Technology, Ghana

Hair tools such as hairbrushes and combs allow for various styling options to produce desired hairstyles among various people. However, there is the risk of they serving as fomites for infection and contamination especially among people in close habitation. This study therefore decided to investigate the trend of microbial population on these hair grooming tools in universities such as KNUST to inform student hygiene practices and disease prevention strategies. 30 students were randomly selected for the study, and swab samples from different hairbrushes and combs were taken for microbial investigation. Microbial isolates were identified based on their morphological biochemical characteristics. Determination of efficacy of different cleaning methods for hair tools was also done. The study found an average bacterial and fungal count of 7.4x102 CFU/ml and 4.6x103 CFU/ml, respectively. The bacterial isolates suspected included Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus sp., Bacillus subtilis, and Corynebacterium sp. The fungal isolates included Aspergillus species, Penicillium sp., Rhizopus sp., Neurospora sp., Colletotrichum gloeosporioides, and Curvularia sp. Correlation analysis showed higher bacterial numbers significantly associated with the presence of hair diseases such as dandruff (p=0.046). Water and detergent were found to be the most effective method of eliminating microbial content from hairbrushes and combs. This study uncovered a variety of microbes on KNUST students' combs and hairbrushes, which is evident of microbial contamination. While these numbers are relatively low, this study highlights the need for students to still follow good hygiene procedures and implement efficient cleaning techniques of hair tools, as they may still serve as an ideal environment to harbor and transfer microbes. Keywords: Hair tools, hairbrushes, microbial load, bacteria, fungi, cleaning methods.

microbiology↗

Promiscuous NAD-dependent dehydrogenases enable efficient bacterial growth on the PET monomer ethylene glycol

Ethylene glycol is widely used as antifreeze agent and monomer of the ubiquitous plastic PET (polyethylene terephthalate). Its global production amounts to more than 50 million tons per year, and it constitutes an environmental pollutant of increasing concern. Although it is generally accepted that bacteria oxidize ethylene glycol to use it as growth substrate, the enzymes involved in this process are not well understood. Here we show that the soil bacterium Paracoccus denitrificans is able to assimilate ethylene glycol efficiently via NAD-dependent alcohol and aldehyde dehydrogenases. Using comparative proteome analysis, we identify a previously unknown gene cluster that is strongly expressed in the presence of ethylene glycol. We report the kinetic parameters and cryo-EM structures of EtgB and EtgA, the key enzymes encoded by this etg gene cluster. These novel biocatalysts pave the way for more efficient biotechnological conversion of ethylene glycol. We furthermore show that the transcriptional activator EtgR controls expression of the etg gene cluster. Directed evolution of P. denitrificans on ethylene glycol results in faster growing strains, which is enabled by increased activities of EtgB and EtgA. Bioinformatic analysis reveals that the etg gene cluster and variants thereof are widely distributed among Proteobacteria, suggesting a previously underappreciated role of NAD-dependent dehydrogenases in microbial ethylene glycol assimilation.

microbiology↗