Isolation, Oxidation, and Application of Crystalline-Pristine Cellulose: Natural Products That Could End Plastic Waste.

ConspectusGiven this special issue's efforts to highlight the research emanating from HBCUs (Historically Black Colleges and Universities) and the trials and tribulations associated with their research, the authors have presented work associated with the characterization and application of cellulosic materials as renewable products. Despite challenges, the research completed in this laboratory at Tuskegee, a HBCU, hinges upon the many investigations of cellulose as a carbon-neutral, biorenewable material that can potentially replace environmentally unfriendly and hazardous petroleum-based polymers. Although cellulose is one of the most promising candidates, overcoming the challenge of its incompatibility (i.e., lack of good dispersion, interfacial adhesion, etc.) with most hydrophobic polymers due to its hydrophilic nature is critical to usage in plastic products across industries. Chemical isolations via acid hydrolysis and surface functionalities have emerged as new approaches to modulate the surface chemistry of cellulose to improve its compatibility and physical performance within the polymer composites. Recently, we have explored the influence of (1) acid hydrolysis and (2) chemical modifications via surface oxidation to ketones and aldehydes on the resulting macrostructural arrangements and thermal performance and (3) the application of crystalline cellulose as reinforcement agents in ABS (acrylonitrile-butadiene-styrene) composites.XRD structural characterizations of crystalline cellulose isolated from wheat straw under dissimilar acid hydrolysis conditions showed induced alterations in the native cellulose polymorph (CI). Mixing of the native polymorph (CI) with CIII was observed and found to be more prominent under sulfuric acid isolation conditions which is one of the more commonly used methods of chemical isolation. Thermal evaluations using TGA confirmed that the introduction of the mixed polymorphs changed the thermal behavior of the isolated crystalline cellulose. Further, FTIR analysis and Tollens testing of chemically oxidized crystalline cellulose via the Albright-Goldman reaction revealed the transformation of surface OH groups to ketones and aldehydes, respectively. We observed similar macrostructural disruption behavior to that of acid hydrolysis processing (i.e., mixing of polymorphs) for oxidation of crystalline cellulose, which had no negative impacts on the thermal stability of the cellulosic structure. The application of acid-hydrolyzed pristine cellulose (PC) as reinforcement agents in ABS composites showed increased thermal-mechanical performance as revealed by TGA and thermal mechanical analysis (TMA). As the ratio of crystalline cellulose increased, the thermal stability of the ABS composite increased, and at extremely high ratios, increased dimensional stability (i.e., low coefficient of thermal expansion (CTE) value) was observed, expanding the application of ABS plastic products.

Quantitative insights into grapevine anthracnose (Elsinoë ampelina) epidemiology: impact of temperature and leaf age on incubation, lesion development, and sporulation.

Grapevine anthracnose, caused by Elsinoe ampelina, is one of the most devastating diseases for wine and table grapes, particularly in hot, humid regions. This study explores how temperature and leaf age affect incubation and how temperature affects lesion development and sporulation. The influence of temperature and leaf age on incubation period (days) was tested under controlled conditions. Leaves from 1 to 8 days old were inoculated and maintained at temperatures of 5, 10, 15, 20, 25, and 30°C. The time elapsed between inoculation and the emergence of initial lesions was recorded. The effect of temperature on lesion development and sporulation was investigated under vineyard conditions. This was achieved through artificial inoculations, with 17, 11, and 11 inoculations conducted in 2016, 2017, and 2018, respectively. The average incubation period, considering all leaf ages, was 27.50 days at 5°C, 15.10 days at 10°C, 9.70 days at 15°C, 5.90 days at 20°C, 3.70 days at 25°C, and 2.26 days at 30°C. Regardless of temperature, the average incubation period was 3.6, 5.9, 8.3, 9.8, 11.9, 13.4, 15.6, and 17.1 days for leaves 1, 2, 3, 4, 5, 6, 7, and 8 days old respectively. The exponential decay model accurately describes the incubation period as a function of both temperature and leaf age. On average, the relative lesion development (RLD) were 0.00, 0.00, 0.23, 0.47, 0.72, 0.93 0.92, 0.90, 0.94, and 1.0 at 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9 days after inoculation, respectively. The average relative sporulation (RSPO) was 0.03, 0.36, 0.82, 0.96, and 1.0 at 5, 10, 15, 20, and 25 days after inoculation, respectively. Both RDL and RSPO as a function of degree-days (Tbase= 0°C) since inoculation were well described by the logistic function. The rates of change in relative lesion development and relative sporulation were 0.055 and 0.032, respectively. The results of this study provide new quantitative insights into three important stages (monocyclic processes) in the development of grapevine anthracnose caused by E. ampelina.

Mutation in MCL1 predicted loop to helix structural transition stabilizes MCL1-Bax binding interaction favoring cancer cell survival.

Myeloid cell leukemia-1 (MCL1), an anti-apoptotic BCL-2 family protein plays a major role in the control of apoptosis as the regulator of mitochondrial permeability which is deregulated in various solid and hematological malignancies. Interaction of the executioner proteins Bak/Bax with anti-apoptotic MCL1 and its cellular composition determines the apoptotic or survival pathway. Mutations act at various levels in the apoptotic process and can contribute to disease. Single nucleotide polymorphism (SNP) in MCL1 gene was focused as they result in changes in the amino acid sequence and have been associated with tumorigenesis. This study highlighted the deleterious MCL1-Bax stabilizing effect of the mutation V220F on MCL1 structure through computational protein-protein interaction predictions and molecular dynamics simulations. The single point mutation at V220F was selected as it is residing at the hydrophobic core region of BH3 conserved domain, the site of Bax binding. The molecular dynamics simulation studies showed increase in stability of the mutated MCL1 before and after Bax binding comparable with the native MCL1. The clusters from free energy landscape found out structural variation in folding pattern with additional helix near the BH3 domain in the mutated structure. This loop to helix structural change in the mutated complex favored stable interaction of the complex and also induced Bax conformational change. Moreover, molecular mechanics-based binding free energy calculations confirmed increased affinity of Bax toward mutated MCL1. Residue-wise interaction network analysis showed the individual residues in Bax binding responsible for the change in stability and interaction due to the protein mutation. In conclusion, the overall findings from the study reveal that the presence of V220F mutation on MCL1 is responsible for the structural confirmational change leading to disruption of its biological functions which might be responsible for tumorigenesis. The mutation could possibly be used as future diagnostic markers in treating cancers.

Treatment Satisfaction in a Civil Commitment Facility for Sexually Violent Persons.

Evaluating patient satisfaction in therapeutic settings is consistent with a Risk-Needs-Responsivity (RNR) model. This study provides results from a program improvement initiative in a sexually violent person (SVP) civil commitment facility that queried patients and treatment providers about their satisfaction with therapeutic processes and assessment methods. Overall, patients reported high levels of satisfaction with treatment at the facility, with the highest levels of satisfaction on items about being treated with kindness and respect and staff acting professionally. Providers rated current assessment methods such as the Penile Plethysmography (PPG) assessment, polygraph testing, and neuropsychological testing as most helpful for patients in treatment progress; however, patients rated PPG assessment and polygraph testing as the least helpful of the assessments conducted. Soliciting patient feedback periodically could be important for maintaining treatment engagement and discovering opportunities to enhance patient satisfaction to treatment in a SVP civil commitment setting.

Cell wall distraction and biofilm inhibition of marine Streptomyces derived angucycline in methicillin resistant Staphylococcus aureus.

The emergence of life threatening antibiotic resistant pathogens and its associated mortality and morbidity necessitates many new antibiotics from diverse ecological habitats. Marine sponge associated microbes are promising to provide such antimicrobial compounds. In the present study, we report antibacterial and anti-biofilm potential of the angucycline antibiotic 8-O-metyltetrangomycin from Streptomyces sp. SBRK2 isolated from a marine sponge of Gulf of Mannar, Rameswaram, India. Our screening program to tackle methicillin-resistant Staphylococcus aureus (MRSA) drug resistance from marine sponge associated actinobacteria yielded the bioactive strain SBRK2. Based on 16S rRNA gene phylogenetic analysis the isolate was found to closely related with Streptomyces longispororuber NBRC 13488T. In vitro production by agar plate fermentation, solvent based extraction, TLC, HPLC purification and LC-MS based de-replication revealed the bioactive compound as 8-O-metyltetrangomycin. The antibacterial minimum inhibitory concentrations against MRSA was identified as 2 µg/mL. Sub-inhibitory concentration of the compound 8-O-metyltetrangomycin reduced the biofilm formation of S. aureus ATCC25923 and increased the cell surface hydrophobicity index. Scanning electron microscopic observation of the sub-inhibitory concentration exposure revealed a wrinkled membrane surface and slight cellular damage shows the cell wall distracting property of the compound. Zebrafish embryo based toxicity assays exhibited 100 µg/mL of compound as maximal non-lethal concentration which had demonstrated the positive relationship in safety index. The angucycline compound 8-O-metyltetrangomycin could be a potential candidate for the development of anti-biofilm agents against drug resistant pathogens.

Virulence factors and antimicrobial resistance of uropathogenic Escherichia coli (UPEC) isolated from urinary tract infections: a systematic review and meta-analysis.

BACKGROUND: Uropathogenic Escherichia coli (UPEC) are amongst the most frequent causes of urinary tract infections. We report a systematic review and meta-analysis of virulence factors and antimicrobial resistance of UPEC isolated from urinary tract infections. METHODS: A systematic review and meta-analysis were performed using PRISMA guidelines (Research Registry ref. 5874). Data were extracted from PubMed/MEDLINE and ScienceDirect databases for studies published from January 1, 2000 to December 31, 2019. Studies reporting antimicrobial resistance and virulence factors of UPEC isolated in confirmed urinary tract infections (≥105CFU/ml) were eligible. Prevalence of antimicrobial resistance and virulence factors of UPEC were estimated using random-effects meta-analysis model. Estimates with 95% confidence intervals, I-square (I2) statistic, and Cochran's Q test were computed using the score statistic and the exact binomial method by incorporating the Freeman-Tukey double arcsine transformation of proportions. RESULTS: Our search returned 2504 hits, of which 13 studies were included in the meta-analysis, totalling 1888 UPEC isolates. Highest antimicrobial resistance rates were observed among the antibiotic class of tetracycline in 69.1% (498/721), followed by sulphonamides in 59.3% (1119/1888), quinolones in 49.4% (1956/3956), and beta-lactams in 36.9% (4410/11964). Among beta-lactams, high resistance was observed in aminopenicillins in 74.3% (1157/1557) and first generation cephalosporins in 38.8% (370/953). Meanwhile, virulence factors with highest prevalence were immune suppressors (54.1%) followed by adhesins (45.9%). Taken individually, the most observed virulence genes were shiA (92.1%), CSH (80.0%), fimH/MSHA (75.3%), traT (75.1%), sisA (72.2%), iucD (65.7%), iutA (61.8%), kpsMTII (60.6%), and PAI (55.2%). CONCLUSIONS: The increased antibiotic resistance of UPEC isolates was demonstrated and suggested a need for reassessment of empirical therapies in urinary tract infections treatment caused by this pathogen. In addition, this pathotype exhibited diverse surface and secreted virulence factors.

Nature and bioprospecting of haloalkaliphilics: a review.

The haloalkaliphilics are an important subset of extremophiles that grow in salt [upto 33% (wt/vol) NaCl] and alkaline pH (> 9). They are found in hypersaline environments especially in the brines in arid, coastal and deep sea locations, and in alkaline environments, such as soda soils, lakes and deserts. Some authors have described haloalkaliphilic bacteria as moderate halophilic bacteria, but the molecular and classical studies revealed that they belong to moderately to extremely halophilic bacteria and archaea. Organic solutes, such as glycine, betaine and other amino acid derivatives, sugars such as, sucrose and trehalose, and sugar alcohols present in the haloalkaliphilics help for their osmoadaptation, and also serve as stabilizers. Haloalkalphilics secrete exoenzymes like proteases, amylases, xylanases, cellulases and peroxidases which have potential industrial applications. They also produce bacteriorhodopsin, compatible solutes, pigments, biopolymers, secondary metabolites like biosurfactants, polyhydroxyalkanoate (PHA) and exopolysaccharides and antimicrobial/anticancer compounds. They have unique metabolic pathways which can be used to treat industrial pollutants, heavy metals and waste water.

HR-LC-MS based analysis of two antibacterial metabolites from a marine sponge symbiont Streptomyces pharmamarensis ICN40.

On the effort to screen antibiotics against Methicillin resistant Staphylococcus aureus (MRSA), an actinomycete strain which can produce bactericidal compound was isolated from a marine sponge of Kanyakumari Coast, India. Two anti-MRSA compounds (PVI401 and PVI402) were isolated from the fermentation plates of Streptomyces pharmamarensis ICN40. TLC bioautography analysis yielded two active spots with Rf value of 0.75 (PVI401) and 0.8 (PVI402) from the crude extract. Both the compounds were characterized by HR-LC-MS analysis. LC-MS based de-replication analysis found out the compound PVI401 with an exact mass of 376.09435 Da and PVI402 with an exact mass of 273.26795 Da were found to be unidentified. Antibacterial spectrum showed significant minimal inhibitory concentration as 0.5 µg/ml of PVI401 and 2 µg/ml of PVI402 against MRSA. The whole organism zebrafish safety evaluation exhibited the compound PVI402 is safe upto 1 mg/ml 40 µg/ml of PVI401 exhibited thrombosis in cardiac chamber and this compound exhibited 44 µg/ml of LC50 against HepG2 hepatic carcinoma cell line. Both the compounds may be identified further for its structural novelty and clinical studies.

In vivo safety evaluation of antibacterial silver chloride nanoparticles from Streptomyces exfoliatus ICN25 in zebrafish embryos.

Silver chloride nanoparticles were synthesized from the cell-free culture supernatant of Streptomyces strain using green synthesis approach with good yield. The nanoparticles were characterized by UV-Vis, IR, SEM, AFM and XRD techniques. These nanoparticles exhibited broad spectrum of antibacterial activity towards Methicillin-resistant Staphylococcus aureus, Methicillin sensitive S. aureus, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumonia at ≤ 2 µg/ml minimal inhibitory concentrations. In vivo bioassay in nanoparticles treated zebrafish embryos exhibited 16 µg/ml dose as maximal cardiac safety concentration and further increases in concentration revealed adverse effects such as pericardial bulging, mouth protrudation, hemorrhage and yolk sac elongation. The less toxicity of nanoparticles treated embryos in terms of cardiac assessment and lethality analysis was observed. The dose below 5 µg/ml is concluded as an in vitro and in vivo therapeutic dose. The properties of this biosynthesized nanoparticle suggest a path towards developing antibiotic nanoparticles that are likely to avoid development of multidrug resistance.

Production of a compound against methicillin resistant Staphylococcus aureus (MRSA) from Streptomyces rubrolavendulae ICN3 & its evaluation in zebrafish embryos.

BACKGROUND & OBJECTIVES: Antibiotic resistance in pathogens has become a serious problem worldwide. Therefore, the search for new antibiotics for drug resistanct pathogens is an important endeavor. The present study deals with the production of anti-methicillin resistant Staphylococcus aureus (MRSA) potential of Streptomyces rubrolavendulae ICN3 and evaluation of anti-MRSA compound in zebrafish embryos. METHODS: The antibiotic production from S. rubrolavendulae ICN3 was optimized in solid state fermentation and extracted. The antagonistic activity was confirmed against MRSA and purified in silica gel column and reverse phase--HPLC with an absorption maximum at 215 nm. Minimal inhibitory concentration of the compound was determined by broth microdilution method. Zebrafish embryos were used to evaluate the extract/compound for its minimal inhibition studies, influences on heart beat rates, haematopoietic blood cell count and lethal dose values. RESULTS: Streptomyces rubrolavendulae ICN3 showed potent antagonistic activity against MRSA with a zone of 42 mm. The minimum inhibitory concentration was calculated as 500 µg/ml of the crude extract and the purified C23 exhibited 2.5 µg/ml in in vitro assay. The LC 50 value of the anti MRSA compound C23 was calculated as 60.49 µg/ml and the MRSA treated embryos survived in the presence of purified compound C23 at a dose of 10 µg/ml. INTERPRETATION & CONCLUSIONS: Our results suggested that the compound was potent with less toxic effects in zebrafish embryonic model system for MRSA infection. Further structural evaluation and analysis in higher mammalian model system may lead to a novel drug candidate for drug resistant Staphylococcus aureus.

Medium optimization for the production of fibrinolytic enzyme by Paenibacillus sp. IND8 using response surface methodology.

Production of fibrinolytic enzyme by a newly isolated Paenibacillus sp. IND8 was optimized using wheat bran in solid state fermentation. A 2(5) full factorial design (first-order model) was applied to elucidate the key factors as moisture, pH, sucrose, yeast extract, and sodium dihydrogen phosphate. Statistical analysis of the results has shown that moisture, sucrose, and sodium dihydrogen phosphate have the most significant effects on fibrinolytic enzymes production (P < 0.05). Central composite design (CCD) was used to determine the optimal concentrations of these three components and the experimental results were fitted with a second-order polynomial model at 95% level (P < 0.05). Overall, 4.5-fold increase in fibrinolytic enzyme production was achieved in the optimized medium as compared with the unoptimized medium.

Draft genome sequence of Streptomyces sp. strain ICN988, isolated from Gorgonia sp.

This study elucidates the draft genomic sequence of Streptomyces sp. strain ICN988, an actinomycete isolated from Gorgonia. The assembled genome consists of 6,122,654 bp with a GC content of 73%. A comprehensive analysis revealed 19 biosynthetic gene clusters.

Household costs and care seeking patterns associated with COVID-19 in Blantyre, Malawi.

Economic consequences of COVID-19 illness and healthcare use for households in low income countries are not well known. We estimated costs associated with COVID-19 care-seeking and treatment from a household perspective and assessed determinants of treatment costs. A cross-sectional household survey was conducted between December 2020 and November 2021 in urban and peri-urban areas of Blantyre district. Adults (age ≥18 years) with confirmed COVID-19 were asked to report the symptoms they experienced or prompted them to seek COVID-19 tests as well as healthcare seeking behaviors preceding and following COVID-19 diagnosis. For individuals who sought healthcare, information on out-of-pocket expenditures incurred while seeking and receiving care including on transport, food etc. by both the patients and their guardians was collected. Finally, data on time use seeking, receiving care and during convalesces was recorded. Multivariate Generalized Linear Models were used to evaluate association between household COVID-19 costs and their determinants. Of 171 individuals who took part in the study, the average age was 40.7 years, standard deviation (SD) 15.0, and 50.8% were females. Most participants (85.3%) were symptomatic. Of these, 67.8% sought care at health facilities and the majority (91.7%) were treated as outpatients. The average total household cost associated with COVID-19 seeking, receiving care and convalescence was $62.81 (SD $126.02). Average costs for outpatient and inpatient cases were $52.96 (SD $54.35) and $172.39 (SD $407.08), respectively. Average out-of-pocket household expenditures were $42.62 (SD $123.10), accounting for 62% of total household costs. Being a male COVID-19 patient and engagement in formal employment were significantly associated with high COVID-19 household costs. Households face high economic burden related to COVID-19 sickness and healthcare use. Social policies that support households cope with both the direct and indirect COVID-19 cost are needed to ensure access to healthcare and protect households from COVID-19 related shocks.

Immediate skin-to-skin contact for low birth weight infants is safe in terms of cardiorespiratory stability in limited-resource settings.

Aim: To investigate the safety of skin-to-skin contact initiated immediately after birth on cardiorespiratory parameters in unstable low birth weight infants. Methods: A randomized clinical trial was conducted in tertiary newborn units in Ghana, India, Malawi, Nigeria and Tanzania in 2017-2020, in infants with birth weight 1.0-1.799 kg. The intervention was Kangaroo mother care initiated immediately after birth and continued until discharge compared to conventional care with Kangaroo mother care initiated after meeting stability criteria. The results of the primary study showed that immediate Kangaroo mother care reduced neonatal mortality by 25% and the results have been published previously. The post-hoc outcomes of this study were mean heart rate, respiratory rate, oxygen saturation during the first four days and the need of respiratory support. Results: 1,602 infants were allocated to control and 1,609 to intervention. Mean birth weight was 1.5 kg (SD 0.2) and mean gestational age was 32.6 weeks (SD 2.9). Infants in the control group had a mean heart rate 1.4 beats per minute higher (95% CI -0.3-3.1, p = 0.097), a mean respiratory rate 0.4 breaths per minute higher (-0.7-1.5, p = 0.48) and a mean oxygen saturation 0.3% higher (95% CI -0.1-0.7, p = 0.14) than infants in the intervention group. Conclusion: There were no significant differences in cardiorespiratory parameters during the first four postnatal days. Skin-to-skin contact starting immediately after birth is safe in low birth weight infants in limited-resource settings.

Draft Genome Sequence of Streptomyces sp. Strain ICN903, Isolated from a Seaweed.

Here, we report the whole-genome sequence of the actinomycete Streptomyces sp. strain ICN903, which was isolated from seaweed of the genus Botryocladia. The whole-genome assembly contained 6,122,654 bp with 73% GC content. In total, 19 biosynthetic gene clusters (BGCs), including polyketides and terpenes, were predicted within the sequenced genome.

Quality of life of primary caregivers of children living with cerebral palsy at two clinics in Blantyre, Malawi.

Introduction: In Malawi, Primary Caregivers (PCGs) of children living with Cerebral Palsy report challenges such as physical strain and lack of resources that affect care giving. Although such experiences affect the PCGs' Quality of Life (QoL), there is paucity of data for Malawi. Understanding their QoL would inform establishment of holistic intervention(s) tailored to meet their needs. Therefore, the purposes of this study were to determine QoL of PCGs of the children who were receiving rehabilitation at Queen Elizabeth Central Hospital (QECH) and Feed the Children (FtC), to identify PCG's and children's socio-demographic factors that may attribute to the perceived QoL, and to compare the PCGs' QoL between the sites. Methods: A cross-sectional study was conducted from January to April 2019 on 142 PCGs of children aged between 2 and 18 years of age. All PCGs who were employed for the child-care, or had a chronic sickness were excluded. QoL was assessed using the World Health Organization Brief questionnaire, with a cut-off point of <60% for poor QoL. The severity of children's impairments was assessed using Gross Motor Function Classification System. Descriptive and inferential statistics were conducted to analyze the data. The PCGs' age, sex, marital status and level of education, and child's severity of impairment were compared with QoL. Results: The majority of PCGs (61.30%) had poor QoL, and there was no significant difference in overall QoL of the PCGs between the sites (p<0.31). The PCGs at QECH had significantly higher physical domain mean scores than at FtC (U=1906, p<0.01). The overall QoL differed significantly across the marital statuses of the PCGs (p<0.03). Conclusion: The study has established that most PCGs at both sites possess poor QoL. However, there is need to investigate how the rehabilitation institutions and workers influence the QoL of the PCGs within and between the facilities.

Mining of transcriptome identifies CD109 and LRP12 as possible biomarkers and deregulation mechanism of T cell receptor pathway in Acute Myeloid Leukemia.

Acute Myeloid Leukemia (AML) is a heterogeneous disease with highest mortality compared to other types of leukemia. There is a need to find the gene abnormalities and mechanisms behind them due to their heterogenic nature. The present study is aimed to understand genes, pathways and biomarker proteins influenced by transcriptomic deregulation due to AML. Differentially expressed gene (DEG), protein-protein interaction network, gene ontology, KEGG pathway, variant analysis and secretome analyses were performed using different AML RNAseq datasets. A total of 655 DEGs including 291 up-regulated and 364 down-regulated genes, which were satisfied with a fold change of 1.5 were identified. Top hub genes for AML were identified as TP53, PTPRC and AKT1. This integrative bioinformatics approach revealed the deregulation of T Cell Receptor (TCR) pathway and altered immune response related genes. The survival analysis revealed the associated deregulation of multiple TCR pathway related genes. Variant analysis identified the benign and likely benign nature of many important target genes and markers screened, which were found to have an important role in the progression of AML. DEGs and secretome analysis found out a set of seven molecules represents potential biomarkers for AML. In vitro analytical validation showed overexpression pattern of CD109 and LRP12 in AML cell line and HL-60 cells than the normal human bone marrow-derived stromal cell line HS-5. Here we report first time for CD109 and LRP12 as a possible biomarkers for the diagnostic significance. Amino acid substitutions detected by variant analysis and deregulation of immune checkpoint molecules revealed their role in reducing immune response and inability to fight cancer cells. In conclusion, this study highlights the possibility of new biomarkers for AML and the mechanism of decrease in immune response due to the downregulation of co-stimulatory immune molecules, which needs further clinical validation investigations.

Multivariate characterisation of morpho-biometric traits of indigenous helmeted Guinea fowl (Numida meleagris) in Nigeria.

This study was conducted to characterise phenotypically helmeted Guinea fowls in three agro-ecologies in Nigeria using multivariate approach. Eighteen biometric characters, four morphological indices and eleven qualitative physical traits were investigated in a total of 569 adult birds (158 males and 411 females). Descriptive statistics, non-parametric Kruskal-Wallis H test followed by the Mann-Whitney U and Dunn-Bonferroni tests for post hoc, Multiple Correspondence Analysis (MCA), Univariate Analysis, Canonical Discriminant Analysis, Categorical Principal Component Analysis and Decision Trees were employed to discern the effects of agro-ecological zone and sex on the morphostructural parameters. Agro-ecology had significant effect (P<0.05; P<0.01) on all the colour traits. In general, the most frequently observed colour phenotype of Guinea fowl had pearl plumage colour (54.0%), pale red skin colour (94.2%), black shank colour (68.7%), brown eye colour (49.7%), white earlobe colour (54.8%) and brown helmet colour (72.6%). The frequencies of helmet shape and wattle size were significantly influenced (P<0.01) by agro-ecology and sex. Overall, birds from the Southern Guinea Savanna zone had significantly higher values (P<0.05) for most biometric traits compared to their Sudano-Sahelian and Tropical Rainforest counterparts. They were also more compact (120.00 vs. 110.00 vs. 107.69) but had lesser condition index (7.66 vs. 9.45 vs. 9.30) and lower long-leggedness (19.71 vs. 19.23 vs. 9.51) than their counterparts from the two other zones. Sexual dimorphism (P<0.05) was in favour of male birds especially those in Southern Guinea Savanna and Sudano-Sahelian zones. However, the MCA and discriminant analysis revealed considerable intermingling of the qualitative physical traits, biometric traits and body indices especially between the Sudano-Sahelian and Tropical Rainforest birds. In spite of the high level of genetic admixture, the Guinea fowl populations could to a relative extent be distinguished using wing length, body length and eye colour. Generally, the birds from the three zones appeared to be more homogeneous than heterogeneous in nature. However, further complementary work on genomics will guide future selection and breeding programs geared towards improving the productivity, survival and environmental adaptation of indigenous helmeted Guinea fowls in the tropics.

ß-lactamase inhibitory potential of kalafungin from marine Streptomyces in Staphylococcus aureus infected zebrafish.

ß-lactamase inhibitors are potent synergistic drugs to deteriorate the multidrug-resistant bacteria. Here, we report the ß-lactamase inhibitory ability of kalafungin isolated from a marine sponge derived Streptomyces sp. SBRK1. The IC50 value of the kalafungin was calculated as 225.37 ± 1.95 µM against ß-lactamase. The enzyme kinetic analysis showed the Km value of 3.448 ± 0.7 µM and Vmax value of 215.356 ± 8 µM/min and the inhibition mechanism was identified as uncompetitive type. Along with the antibacterial activity, the cell surface analysis of kalafungin treated Staphylococcus aureus cells revealed destruction of cell membrane in response to ß-lactamase inhibition. Molecular docking studies have confirmed the binding property of kalafungin against ß-lactamase with two hydrogen bonds. In vivo efficacy studies in the zebrafish model by green fluorescent protein expressing S. aureus infection, survival, safety and behavioral profile were reported. The toxicity and anti-infection revealed that the compound was evidently active and safe to all organs. In conclusion, this is the first report on kalafungin with ß- lactamase inhibition and suggests that kalafungin may useful for synergic antibacterial therapy with ß-lactam drugs to overcome ß-lactamase-based resistance of any bacterial pathogens.

Streptomyces marianii sp. nov., a novel marine actinomycete from southern coast of India.

A novel marine actinomycete strain designated ICN19T was isolated from the subtidal sediment of Chinnamuttam coast of Kanyakumari, India and subjected to polyphasic taxonomic analysis. Neighbour-joining tree based on 16S rRNA gene sequences of validly described type strains had revealed the strain ICN19T formed distinct cluster with Streptomyces wuyuanensis CGMCC 4.7042T, Streptomyces tirandamycinicus HNM0039T and Streptomyces spongiicola HNM0071T. Morphological, physiological and chemotaxonomic characteristics were consistent with those of members of the genus Streptomyces. The strain possessed LL-diaminopimelic acid as the diagnostic diamino acid. The predominant isoprenoid quinone was identified as MK-9(H8) (70%), MK-9(H6) (20%) and MK-9(H2) (2%), with the major cellular fatty acids (>10%) being anteiso-C15:0, C16:0 and iso-C16:0. The main polar lipids were found to be diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol mannosides and three unidentified phospholipids. The dendrogram generated on the basis of MALDI-TOF mass spectra supports the strain differentiated from its neigbours. The genome sequence of strain ICN19T was 9,010,366 bp in size with a total of 7420 protein-coding genes and 98 RNA genes. The genomic G+C content of the novel strain was 71.27 mol%. The DNA-DNA relatedness between strain ICN19T and the reference strains with S. wuyuanensis CGMCC 4.7042T, S. tirandamycinicus HNM0039T and S. spongiicola HNM0071T were 42.8%, 39.5% and 38%, respectively. Based on differences in physiological, biochemical, chemotaxonomic differences and whole-genome characteristics the isolated strain represents a novel species of the genus Streptomyces, for which the name Streptomyces marianii sp. nov. is proposed. Type strain is ICN19T (=MCC 3599T = KCTC 39749T).