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Molecular cloning, homology modeling and site-directed mutagenesis of vanadium-dependent bromoperoxidase (GcVBPO1) from Gracilaria changii (Rhodophyta)

Baharum H, Chu WC, Teo SS, Ng KY, Rahim RA, Ho CL

Phytochemistry, 2013 Aug;92:49-59.
PMID: 23684235 DOI: 10.1016/j.phytochem.2013.04.014

Vanadium-dependent haloperoxidases belong to a class of vanadium enzymes that may have potential industrial and pharmaceutical applications due to their high stability. In this study, the 5'-flanking genomic sequence and complete reading frame encoding vanadium-dependent bromoperoxidase (GcVBPO1) was cloned from the red seaweed, Fracilaria changii, and the recombinant protein was biochemically characterized. The deduced amino acid sequence of GcVBPO1 is 1818 nucleotides in length, sharing 49% identity with the vanadium-dependent bromoperoxidases from Corralina officinalis and Cor. pilulifera, respectively. The amino acid residues associated with the binding site of vanadate cofactor were found to be conserved. The Km value of recombinant GcVBPO1 for Br(-) was 4.69 mM, while its Vmax was 10.61 μkat mg(-1) at pH 7. Substitution of Arg(379) with His(379) in the recombinant protein caused a lower affinity for Br(-), while substitution of Arg(379) with Phe(379) not only increased its affinity for Br(-) but also enabled the mutant enzyme to oxidize Cl(-). The mutant Arg(379)Phe was also found to have a lower affinity for I(-), as compared to the wild-type GcVBPO1 and mutant Arg(379)His. In addition, the Arg(379)Phe mutant has a slightly higher affinity for H2O2 compared to the wild-type GcVBPO1. Multiple cis-acting regulatory elements associated with light response, hormone signaling, and meristem expression were detected at the 5'-flanking genomic sequence of GcVBPO1. The transcript abundance of GcVBPO1 was relatively higher in seaweed samples treated with 50 parts per thousand (ppt) artificial seawater (ASW) compared to those treated in 10 and 30 ppt ASW, in support of its role in the abiotic stress response of seaweed.
Fulltext Validating an Instrument for Measuring Newly Graduated Nurses' Adaptation

Baharum H, Ismail A, Awang Z, McKenna L, Ibrahim R, Mohamed Z, et al.

Int J Environ Res Public Health, 2023 Feb 06;20(4).
PMID: 36833559 DOI: 10.3390/ijerph20042860

A long-established approach, Confirmatory Factor Analysis (CFA) is used to validate measurement models of latent constructs. Employing CFA can be useful for assessing the validity and reliability of such models. The study adapted previous instruments and modified them to suit the current setting. The new measurement model is termed NENA-q. Exploratory factor analysis (EFA) revealed the instruments of the NENA-q model formed a construct of the second order with four dimensions, namely organizational contribution (OC), academic institution contribution (AIC), personality traits (PT), and newly employed nurses' adaptation (NENA). Researchers administered the questionnaires to a sample of 496 newly employed nurses working in hospitals under the Ministry of Health (MOH) for the confirmation of the extracted dimensions. The study performed a two-step CFA procedure to validate NENA-q since the model involves higher-order constructs. The first step was individual CFA, while the second step was pooled CFA. The validation procedure through confirmatory factor analysis (CFA) found the model achieved the threshold of construct validity through fitness index assessment. The model also achieved convergent validity when all average variance extracted (AVE) exceeded the threshold value of greater than 0.5. The assessment of the composite reliability (CR) value indicates all CR values exceeded the threshold value of 0.6, which indicates the construct achieved composite reliability. Overall, the NENA-q model consisting of the OC construct, AIC construct, PT construct, and NENA construct for CFA has met the fitness indexes and passed the measurements of the AVE, CR, and normality test. Once the measurement models have been validated through CFA procedure, the researcher can assemble these constructs into structural model and estimate the required parameter through structural equation modelling (SEM) procedure.
Success factors in adaptation of newly graduated nurses: a scoping review

Baharum H, Ismail A, McKenna L, Mohamed Z, Ibrahim R, Hassan NH

BMC Nurs, 2023 Apr 18;22(1):125.
PMID: 37069647 DOI: 10.1186/s12912-023-01300-1

BACKGROUND: Difficulties in adapting to the workplace can affect newly graduated nurses' transition. Such nurses must adapt quickly, as it can affect their future career prospects. Therefore, this review aimed to identify the success factors that promote newly graduated nurses' effective transition and adaptation.
METHODS: The Joanna Briggs Institute scoping reviews methodology was used. Data were extracted from MEDLINE, Scopus, EBSCOhost, and Web of Science publications published between 2011 and 2020. A total of 23 articles were included in this review, which comprised qualitative, quantitative, and mixed methods primary research studies focusing on the contributing factors that aided newly graduated nurses' adaptation to the work environment during their transition period. Key emerging themes were identified with thematic analysis.
RESULTS: Three main themes were identified: (1) organisational contribution (social development, organisational culture, work characteristics, work readiness, work commitment, professional role), (2) personality traits (self-embodiment, personality masking, being proactive and confident), and (3) academic institutions (pre-entry knowledge and role of nursing faculty). Newly graduated nurses' adaptation should begin during nursing education, be supported by the workplace organisation, and driven by the nurse's personality. We determined that that the role of nursing education in aiding the provision of the required knowledge and actual clinical experiences to students profoundly affected developing nurses' self-confidence levels in delivering nursing care effectively. Additionally, a warm environment supported nurses emotionally and physically.
CONCLUSIONS: While organisations and educational institutions have undertaken numerous efforts to ensure that newly graduated nurses are adequately supported, the nurse's personality and values are also equally important to ease adaptation during the transition process. Academic and workplace programs designed for newly graduated nurses should apply and emphasise this knowledge to develop and strengthen their personalities and values, especially to increase confidence and promote proactive values that facilitate newly graduated nurses' rapid and effective adaptation to their new employment.
Molecular cloning, modeling, and site-directed mutagenesis of type III polyketide synthase from Sargassum binderi (Phaeophyta)

Baharum H, Morita H, Tomitsuka A, Lee FC, Ng KY, Rahim RA, et al.

Mar Biotechnol (NY), 2011 Oct;13(5):845-56.
PMID: 21181422 DOI: 10.1007/s10126-010-9344-5

Type III polyketide synthases (PKSs) produce an array of metabolites with diverse functions. In this study, we have cloned the complete reading frame encoding type III PKS (SbPKS) from a brown seaweed, Sargassum binderi, and characterized the activity of its recombinant protein biochemically. The deduced amino acid sequence of SbPKS is 414 residues in length, sharing a higher sequence similarity with bacterial PKSs (38% identity) than with plant PKSs. The Cys-His-Asn catalytic triad of PKS is conserved in SbPKS with differences in some of the residues lining the active and CoA binding sites. The wild-type SbPKS displayed broad starter substrate specificity to aliphatic long-chain acyl-CoAs (C(6)-C(14)) to produce tri- and tetraketide pyrones. Mutations at H(331) and N(364) caused complete loss of its activity, thus suggesting that these two residues are the catalytic residues for SbPKS as in other type III PKSs. Furthermore, H227G, H227G/L366V substitutions resulted in increased tetraketide-forming activity, while wild-type SbPKS produces triketide α-pyrone as a major product. On the other hand, mutant H227G/L366V/F93A/V95A demonstrated a dramatic decrease of tetraketide pyrone formation. These observations suggest that His(227) and Leu(366) play an important role for the polyketide elongation reaction in SbPKS. The conformational changes in protein structure especially the cavity of the active site may have more significant effect to the activity of SbPKS compared with changes in individual residues.