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Kalpana M Angadi,1 Vivekanand B Jadhav,2 Savita V Jadhav1 1Symbiosis Medical College for Women (SMCW) & Symbiosis University Hospital and Research Centre (SUHRC), Symbiosis International (Deemed University), Pune, India; 2Dr. Naidu Infectious Diseases Hospital, Pune Municipal Corporation Pune Maharashtra, Pune, IndiaCorrespondence: Savita V Jadhav, Email savita.jadhav@smcw.siu.edu.in View the original paper by Mr Alelign and colleagues

Acinetobacter baumannii and Enterococcus faecalis are opportunistic bacteria frequently associated with hospital-acquired infections. A. baumannii nosocomial infections in intensive care units are a worldwide problem, with high mortality rates. It may also develop rapidly multidrug resistance (MDR), extensive drug resistance (XDR), and even pan-drug resistance (PDR). Colistin resistance which is an example of pan-drug resistance, is highly alarming as it's used as a last-line antibiotic. Microbes capable of crossing epithelial barriers such as E. faecalis have developed novel strategies to counter antimicrobial agents and cause bacteremia in immunocompromised patients. However, the coinfection of these bacteria in the same patient is unusual. Here, we report a genomic investigation of the extensively drug-resistant E. faecalis and A. baumannii isolated from the blood sample of a patient diagnosed with pauci-immune crescentic glomerulonephritis (PICGN). Identification of cultures isolated from blood sample was carried out using whole-genome sequencing and resistome profiles were mapped. Whole genome sequencing revealed that E. faecalis SVJ-EF01 had a genome size of 2,935,226 bp and GC content of 37.4%, whereas A. baumannii SVJ-AC01 had a genome size of 3,730,857 bp and GC content of 39%. Draft genomes were functionally annotated demonstrating that the organism harbors multiple virulence factors and antimicrobial-resistant mechanisms including MDR efflux pumps. A. baumannii genome possessed a CRISPR-Cas system which might contribute to antimicrobial resistance. This highlights the significance of polymicrobial nature in ESKAPE pathogenesis research. This genomic investigation helps to gain insights into the virulence, resistance profile, and functional potential of these pathogens., Competing Interests: Declarations. Conflict of interest: The authors declare no conflict of interest. Ethical Approval: This article did not require any ethical approval., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Aims: Klebsiella pneumoniae is a Gram-negative bacterium that can colonize, penetrate, and cause infections at several human anatomical locations. The emergence of hypervirulent K. pneumoniae and its ability to evade the immune system and develop antibiotic resistance has made it a key concern in the healthcare industry. The hypervirulent variants are increasingly involved in community-acquired infections. Therefore, it is pertinent to understand the biofilm formation potential among the clinical isolates., Methods and Results: We acquired 225 isolates of K. pneumoniae from the Department of Microbiology, Symbiosis University Hospital and Research Centre (SUHRC), Pune, India, over 1 year from March 2022 to March 2023, and evaluated antimicrobial susceptibility, hypermucoviscous phenotype, virulence, and antimicrobial-resistant gene distribution in K. pneumoniae isolates and established a correlation between antimicrobial resistance and integrons. Most isolates were strong biofilm formers (76%). The isolates harbored one or more carbapenemase/beta-lactamase-encoding gene combinations. Hypermucoviscous (HMKP) isolates had considerably greater positive rates for iutA, magA, K2 serotype, rmpA, and rmpA2 than non-HMKP isolates. Isolates carrying integrons (43%) showed significantly more antibiotic resistance., Conclusion: The study reveals spread of strong biofilm formers with extensive virulence and antimicrobial-resistant genes, and integrons responsible for multidrug resistance among the clinical isolates of K. pneumoniae in Pune, India, posing a threat to the public health and necessitating close surveillance, accurate diagnosis, control, and therapeutic management of infections., (© The Author(s) 2024. Published by Oxford University Press on behalf of Applied Microbiology International.)

Context: Activation of fibroblast growth factor receptor 1 (FGFR1) signaling improves the metabolic health of animals and humans, while inactivation leads to diabetes in mice. Direct human genetic evidence for the role of FGFR1 signaling in human metabolic health has not been fully established., Objective: We hypothesized that individuals with naturally occurring FGFR1 variants ("experiments of nature") will display glucose dysregulation., Methods: Participants with rare FGFR1 variants and noncarrier controls. Using a recall-by-genotype approach, we examined the β-cell function and insulin sensitivity of 9 individuals with rare FGFR1 deleterious variants compared to 27 noncarrier controls, during a frequently sampled intravenous glucose tolerance test at the Reproductive Endocrine Unit and the Harvard Center for Reproductive Medicine, Massachusetts General Hospital. FGFR1 -mutation carriers displayed higher β-cell function in the face of lower insulin sensitivity compared to controls., Conclusion: These findings suggest that impaired FGFR1 signaling may contribute to an early insulin resistance phase of diabetes pathogenesis and support the candidacy of the FGFR1 signaling pathway as a therapeutic target for improving the human metabolic health., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society.)

Silver nanoclusters (AgNCs) have emerged as versatile nanomaterials with immense potential in theranostic applications, combining therapeutic and diagnostic functions in a single platform. This review provides a comprehensive overview of recent advancements in the synthesis, characterization, and utilization of AgNCs for theranostics. The synthesis of AgNCs has witnessed significant progress, with numerous strategies such as chemical reduction, green synthesis, and templated approaches being employed to control size, shape, and stability. Their unique optical properties, including strong fluorescence and surface-enhanced Raman scattering (SERS) signals, make AgNCs ideal candidates for bioimaging and diagnostic purposes. Additionally, the surface chemistry of AgNCs allows for facile functionalization with targeting ligands and therapeutic agents, enhancing their specificity and efficacy. In the realm of diagnostics, AgNCs have been employed for various imaging modalities, including fluorescence imaging, photoacoustic imaging, and SERS-based sensing. Their excellent photostability and biocompatibility make them suitable for in vitro and in vivo imaging applications, enabling the real-time monitoring of disease progression and treatment response.

Background and Objectives: Methicillin resistance is acquired by the bacterium due to mecA gene which codes for penicillin-binding protein (PBP2a) having low affinity for β-lactam antibiotics. mecA gene is located on a mobile genetic element called staphylococcal cassette chromosome mec (SCC mec ). SCC mec genomic island comprises two site-specific recombinase genes namely ccrA and ccrB [cassette chromosome recombinase] accountable for mobility. Currently, SCC mec elements are classified into types I, II, III, IV and V based on the nature of the mec and ccr gene complexes and are further classified into subtypes according to variances in their J region DNA. SSC mec type IV has been found in community-acquired isolates with various genetic backgrounds. The present study was undertaken to categorize the types of SCC mec types and subtypes I, II, III, IVa, b, c, d, and V and PVL genes among clinical MRSA isolates from COVID-19 confirmed cases., Materials and Methods: Based on the Microbiological and Molecular ( mecA gene PCR amplification) confirmation of MRSA isolated from 500 MRSA SCC mec clinical samples, 144 cultures were selected for multiplex analysis. The multiplex PCR method developed by Zhang et al. was adapted with some experimental alterations to determine the specific type of these isolates., Results: Of the total 500 MRSA, 144 MRSA (60 were CA-MRSA and 84 were HA-MRSA) were selected for characterization of novel multiplex PCR assay for SSC mec Types I to V in MRSA. Molecular characterization of multiplex PCR analysis revealed results compare to the phenotypic results. Of the 60 CA-MRSA; in 56 MRSA strains type IVa was found and significantly defined as CA-MRSA while 4 strains showed mixed gens subtypes. Type II, III, IA, and V were present in overall 84 HA-MRSA. Molecular subtyping was significantly correlated to define molecularly as CA-MRSA and HA-MRSA however 15 (10%) strains showed mixed genes which indicates the alarming finding of changing epidemiology of CA-MRSA and HA-MRSA as well., Conclusion: We have all witnessed of COVID-19 pandemic, and its mortality was mostly associated with co-morbid conditions and secondary infections of MDR pathogens. Rapid detections of causative agents of these superbugs with their changing epidemiology by investing in typing and subtyping clones are obligatory. We have described an assay designed for targeting SSC mec types and subtypes I, II, III, IVa,V according to the current updated SCC mec typing system. Changing patterns of molecular epidemiology has been observed by this newly described assay., (Copyright © 2023 The Authors. Published by Tehran University of Medical Sciences.)

Introduction: The teaching of human anatomy, a medical subject that relies heavily on live teaching, teacher-student interactivity, and visuospatial skills, has suffered tremendously since the COVID-19 pandemic mandated the shutting down of medical institutions. The medical education fraternity was compelled to replace the traditional teaching method of hands-on cadaveric dissections (HOCDs) with online education to overcome this new challenge, but it came at the cost of reduced student engagement and lesser spatial orientation., Method: In this cross-sectional, questionnaire-based study, we designed a novel online dissection course on lower limb anatomy and collected student feedback on the same from consenting Phase I Bachelor of Medicine, Bachelor of Surgery (MBBS) students of Symbiosis Medical College for Women, Pune, India. The course design consisted of three different modes: a live Zoom session using a handheld camera phone, a pre-recorded video dissection uploaded on the institute learning management system, and a Powerpoint presentation with high-resolution photographs of each dissected layer; and the feedback intended to find out what works best for the students. Overall feedback regarding their preferences in terms of presentation design, use of background music in pre-recorded videos, and overall learning experience was also collected. The course consisted of six two-hour teaching sessions. The first three sessions each used a different mode of teaching, repeating the same pattern in the next three sessions. The first mode of teaching implemented was a live Zoom session where instructors used a hand-held cell phone camera to show specimens that had been dissected a day prior. The second mode involved a pre-recorded video showing step-by-step dissection performed by the instructor which was then uploaded on the Institute Learning Management System. Of the two pre-recorded videos, background music consisting of a low-volume instrumental track was added to the second video. The third mode utilized Powerpoint presentations containing high-resolution photographs of each dissected layer on a separate slide along with labeling. The presentations were shown to the students over a Zoom call. A Google Form (GF) questionnaire was created after validation by subject experts to gather the students' feedback on the teaching and learning of anatomy via these sessions. The GF responses were collected and analyzed using Microsoft Excel., Results: 41.7% of students recommended the use of a combination of all three modes in the same session, while 36.7% favored pre-recorded videos. 86.7% of students said that a good quality presentation design helps in keeping them engaged and only 23% of students favored the use of background music for increasing their ability to concentrate. 63.3% of students found the learning experience highly satisfactory., Conclusion: Although virtual dissection teaching methods may not be able to completely replace HOCDs, a well-planned online dissection course incorporating multiple modes of online dissections with an emphasis on good quality presentation design and frequent teacher-student interactivity can provide a strong impetus for learning in the absence of live teaching methods., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Jadhav et al.)

This article outlines the synthesis of gadolinium (Gd)-doped manganese zinc ferrite magnetic nanoparticles (MNPs) as potential magnetic carriers for magnetic fluid hyperthermia (MFH). MNPs with high specific loss power (SLP; 146 W/g) have been developed and used for an in vitro hyperthermia study. The treatment of MFH is fruitful if there is an adequate number of MNPs in tumor cells with the highest SLP to rapidly generate heat while minimizing thermal injury to surrounding healthy tissue. X-ray diffraction patterns of the studied particles confirm the formation of a cubic spinel structure. Field emission scanning electron micrographs showed homogeneous distributions of particles with some agglomerates with a granular appearance. Transmission electron microscopy analysis showed the presence of agglomerated spherical particles at the surface. The substitution of Gd resulted in superparamagnetism at room temperature as confirmed by vibrating sample magnetometer analysis. The estimated saturation magnetization reduced from 48.6 to 28.2 emu/g with an increase in Gd concentration. However, the coercivity increased from 1093 Oe to 1597 Oe. Field cooled and zero field cooled measurements showed Curie temperatures from 315 to 326 K, as required for MFH applications. Cell viability measurements indicated that the MNPs are nontoxic to A549 cells for the studied concentrations of particle fraction and a contact time of up to 24 h. The interaction of the MNPs with A549 cells was highlighted from an image captured by an inverted microscope. In order to treat cancer in vivo, an in vitro hyperthermia study has initially been carried out with A549 cells., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Gabapentin, an antiepileptic drug, is known to form stable helical structures in short peptides. Distinctly, we report on the newly synthesized γ-analogue of gabapentin, that is, γ-gabapentin (γ-Gpn), which manifests β-sheet character at molecular and nanofibrous hydrogels at the supramolecular level. We investigated the influence of proximally immobilized cationic amino acids (lysine and arginine) on the self-assembly of backbone-expanded tripeptide motif. Interestingly, arginine was found to be superior, both physically and mechanically, over lysine in driving hydrogelation. We have concluded that intrinsic and biochemically distinct properties of the guanidinium ion of arginine (compared to ammonium ion of lysine) have contributed towards this effect. Furthermore, similar to pyroglutamyl (pGlu) modified amyloid β peptides, N-pGlu modification of our self-assembling tripeptide motif exerts a dramatic influence on aggregation and exhibits enhanced β-sheet character, accelerated self-assembly kinetics, improved optical transparency and provides higher mechanical stiffness to the peptide hydrogel., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The current research work represents solvent free enzymatic synthesis of fatty acid ethyl ester; ethyl laurate. Immobilized lipase Fermase CALB™10,000 was used for the synthesis of ethyl laurate from ethanol and lauric acid. The influence of process parameters such as catalyst loading, speed of agitation, mole ratio, molecular sieves and temperature were studied. Fermase CALB™10,000 offered a conversion of 92.46 % at 60 °C in 4 h at optimized condition. The experimental data was best fitted by the Random Bi-Bi model with inhibition of both the substrates i.e. lauric acid and ethanol. The following kinetic parameters were retrieved from the model: V max  = 1.243 × 10 3  mmol/min/g enzyme; K A  = 0.1283 mmol; K B  = 8.51 mmol; K iA  = 5.098 mmol; and SSE = 0.0142. The activation energy for the enzymatic esterification was also determined and calculated to be 28.49 kJ/mol. A maximum conversion of 71 % was obtained after 5 successive reuse of Fermase CALB™10,000 lipase.

The current paper exemplifies the application of ultrasound technology to enzymatic synthesis of a cosmetic emollient ester, cetyl oleate. Fermase CALB™10000, a commercial Candida antarctica lipase B was used as a catalyst to accomplish the ultrasound supported synthesis. Multiple process parameters like reaction time, temperature, enzyme dose, alcohol to acid molar ratio, ultrasound power, frequency and speed of agitation were optimised. Maximum conversion of ∼95.96% was discerned at optimum conditions, i.e., 60°C temperature, 5% enzyme dose, 2:1 alcohol:acid ratio, 60 W ultrasound power, 25 kHz ultrasound frequency, 80% duty cycle and 80 rpm speed of agitation after purification steps. It was observed that the reaction reached equilibrium in a short duration of 30 min under the optimised conditions. This was considerably lesser than the time required for attaining equilibrium in conventional mechanical stirring method which was over 2h. Bisubstrate kinetic models like random bi-bi, ping pong bi-bi and ordered bi-bi were applied to the experimental data to determine initial rates and other kinetic parameters. Ordered bi-bi model showed the best fit with kinetic parameters, Vmax=0.029 M/min/gcatalyst, KA=0.00001 M, KB=4.8002 M, KiA=0.00014 M, KiB=3.7914 M & SSE=0.00022 for enzymatic cetyl oleate synthesis under ultrasound irradiation with inhibition by both acid and alcohol at high concentrations., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Chronic contamination of groundwaters by both arsenic (As) and fluoride (F) is frequently observed around the world, which has severely affected millions of people. Fluoride and As are introduced into groundwaters by several sources such as water-rock interactions, anthropogenic activities, and groundwater recharge. Coexistence of these pollutants can have adverse effects due to synergistic and/or antagonistic mechanisms leading to uncertain and complicated health effects, including cancer. Many developing countries are beset with the problem of F and As laden waters, with no affordable technologies to provide clean water supply. The technologies available for the simultaneous removal are akin to chemical treatment, adsorption and membrane processes. However, the presence of competing ions such as phosphate, silicate, nitrate, chloride, carbonate, and sulfate affect the removal efficiency. Highly efficient, low-cost and sustainable technology which could be used by rural populations is of utmost importance for simultaneous removal of both pollutants. This can be realized by using readily available low cost materials coupled with proper disposal units. Synthesis of inexpensive and highly selective nanoadsorbents or nanofunctionalized membranes is required along with encapsulation units to isolate the toxicant loaded materials to avoid their re-entry in aquifers. A vast number of reviews have been published periodically on removal of As or F alone. However, there is a dearth of literature on the simultaneous removal of both. This review critically analyzes this important issue and considers strategies for their removal and safe disposal., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Presence of bacteria such as Brucella spp. in dairy products is an immense risk to public health. Point of care immunoassays are rapid in that they can quickly screen various samples in a relatively short amount of time, are sensitive, specific and offer a great advantage in accurate and fast diagnosis of infectious diseases. We have fabricated a point of care rapid diagnostic assay that employs fluorescent, micellar silica nanosensors capable of specifically detecting Brucella IgG antibodies in milk samples of afflicted animals. Currently, point of care detection assays are not commercially available for field testing of farm animals using milk samples. The nanosensing allows precise detection of antibodies with low sample volumes (50 μl). We demonstrate recognition of B. abortus antibodies through capture by fluorescent silica nanosensors using spiked and raw milk samples validated by ELISA and PCR. The test results are accurate and repeatable with high sensitivity and specificity, and a short assay time of 10 min for antigenic recognition and do not require any sample processing procedures such as isolation and separation. Additionally, well defined antigenic components and surface biomarkers of various disease causing microbes can be broadly incorporated within the purview of this technology for accurate and rapid detection of suspected bovine pathological conditions, and can largely enable rapid field testing that can be implemented in farms and food industry., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Supramolecular assembly of various artificially folded 12-helical architectures composed of γ(4) -Val, γ(4) -Leu and γ(4) -Phe residues is investigated. In contrast to the 12-helices composed of γ(4) -Val and γ(4) -Leu residues, the helices with γ(4) -Phe residues displayed unique elongated nanotubular architectures. The elongated nanotube assembly was further explored as a template for biomineralization of silver ions to silver nanowires. A comparative study using an analogous α-peptide helix reveals the importance of the spatial arrangement of aromatic side chains along the helical cylinder in a 12-helix. These results suggested that the proteolytically and structurally stable α,γ(4) -hybrid peptide 12-helices may serve as a new generation of potential templates in the design of functional biomaterials., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The stability and compatibility of designed coiled coil peptides towards the selective incorporation of γ(4)-amino acids at the hydrophobic positions of the heptad repeat are studied. Investigations reveal that the low thermal denaturation temperature of γ(4)-residue mutated coiled coils can be utilized as a mild hyperthermia trigger in liposomes.

Hybrid peptides composed of α- and β-amino acids have recently emerged as new class of peptide foldamers. Comparatively, γ- and hybrid γ-peptides composed of γ(4) -amino acids are less studied than their β-counterparts. However, recent investigations reveal that γ(4)-amino acids have a higher propensity to fold into ordered helical structures. As amino acid side-chain functional groups play a crucial role in the biological context, the objective of this study was to investigate efficient synthesis of γ(4)-residues with functional proteinogenic side-chains and their structural analysis in hybrid-peptide sequences. Here, the efficient and enantiopure synthesis of various N- and C-terminal free-γ(4)-residues, starting from the benzyl esters (COOBzl) of N-Cbz-protected (E)-α,β-unsaturated γ-amino acids through multiple hydrogenolysis and double-bond reduction in a single-pot catalytic hydrogenation is reported. The crystal conformations of eight unprotected γ(4)-amino acids (γ(4)-Val, γ(4)-Leu, γ(4)-Ile, γ(4)-Thr(OtBu), γ(4)-Tyr, γ(4)-Asp(OtBu), γ(4)-Glu(OtBu), and γ-Aib) reveals that these amino acids adopted a helix favoring gauche conformations along the central C(γ) -C(β) bond. To study the behavior of γ(4)-residues with functional side chains in peptide sequences, two short hybrid γ-peptides P1 (Ac-Aib-γ(4)-Asn-Aib-γ(4)-Leu-Aib-γ(4)-Leu-CONH2 ) and P2 (Ac-Aib-γ(4)-Ser-Aib-γ(4)-Val-Aib-γ(4)-Val-CONH2 ) were designed, synthesized on solid phase, and their 12-helical conformation in single crystals were studied. Remarkably, the γ(4) -Asn residue in P1 facilitates the tetrameric helical aggregations through interhelical H bonding between the side-chain amide groups. Furthermore, the hydroxyl side-chain of γ(4)-Ser in P2 is involved in the interhelical H bonding with the backbone amide group. In addition, the analysis of 87 γ(4)-residues in peptide single-crystals reveal that the γ(4)-residues in 12-helices are more ordered as compared with the 10/12- and 12/14-helices., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Conformational analysis of γ-peptides composed of 4,4-gem-dimethyl γ-amino acids, their spontaneous self-assembly into nanofibrillar superstructures and remarkable thermoreversible gelation properties in various organic solvents are studied. This new generation of γ-peptides may serve as potential templates to design advanced biomaterials.

Background: In the past few years, there has been an increase in infections caused by fungal aetiology. This is mainly due to increase in sizes of populations which are at risk. Also, fungi which were previously considered as non-pathogenic have been increasingly implicated. Hence, this study was taken up., Aim: To assess the magnitude of mycotic infections in this set up. To assess the spectrum of fungi which are involved in various infections., Material and Methods: Total 704 samples taken over two and half period were included. They consisted of various samples like sputum, blood, urine, sterile body fluids, corneal scrapings. These were processed by conventional mycological techniques. These included direct microscopy after Gram staining and KOH mount, culture on Sabouraud's dextrose agar (SDA), corn meal agar, brain heart infusion (BHI), brain heart infusion agar (BHIA) and others, as required. For non-albicans Candida, the automated Vitek 2 C system was used. Various moulds and yeasts were identified up to genus level and species level., Results: Of 704 samples, 336 (48%) were positive for fungal culture. Of these, 244 isolates were yeast like fungi, 81 were moulds, 7 were yeasts and 4 were dimorphic. Among blood stream infections, non-albicans Candida were the commonest isolates. In the urine samples, C. albicans was the commonest isolate. From corneal scrapings, only moulds and dimorphic fungi were isolated., Conclusion: Incidence of non- albicans Candidal infections is increasing. Culture and identification of mycotic infections is essential for commencement of suitable antifungal therapy.

Diagnosing extra-pulmonary tuberculosis is a challenge that can confound even the most practiced clinicians as clinical manifestations are vague, non-specific and typical chest radiograph findings may not be evident till late in the disease. Conventional methods for mycobacteriological culture and drug susceptibility testing are slow and cumbersome. Novel technologies for rapid detection of Mycobacterium tuberculosis and its anti-TB drug resistance have therefore become a priority hence with the development of molecular line probe assays are most advanced. Herewith we are reporting a case of splenic tuberculosis in an immunocompromised patient for its rarity and to emphasis the fact that such patients can be diagnosed early for better treatment outcome to enhance the longevity if a health setup possesses all the modern diagnostic services.

Numerous strategies have been developed to mimic the α-helical secondary structure using hybrid peptides containing non-natural amino acids. In contrast to the β- and α/β-hybrid peptides, very little is known about the folding patterns of hybrid peptides containing γ(4)-amino acids. Here we report the solid phase synthesis and crystallographic insight into the secondary structures formed by 1 : 1 alternating α/γ(4)-hybrid peptides. The crystal conformations suggest that heptapeptides P1, P2 and P3 adopted the 12-helix conformation with backward consecutive 1←4 H-bonds [C=O(i)···H-N (i + 3)]. In comparison with α-, β- and γ-peptides, the distinct projection of side-chains was observed along the helical cylinder. In contrast to the peptide containing stereochemically constrained α-amino acid Aib (P1), the peptide with complete proteinogenic side-chains (P3) displayed organized side chain-side chain interactions between the antiparallel helices in crystal packing. The analogy of the α/γ(4)-hybrid peptides with 3(10)-helix, α-helix and β-peptide 12-helix suggests that the internal H-bonding pattern and macrodipole were analogous to the α- and β-peptide helices. In addition, helical parameters were found to be very similar to that of β-peptide 12-helices.

Synthesis, crystal conformations of α/γ(4)-hybrid peptide helices containing proteinogenic amino acid side-chains, and the analogy with the α-helix are reported. Results suggest that α/γ(4)-hybrid peptides adopted helical conformations with 12-membered H-bond pseudocycles in single crystals.

A novel, ultrafast, mild and scalable amide bond formation strategy in methanol using simple thioacids and amines is described. The mechanism suggests that the coupling reactions are initially mediated by CuSO(4)·5H(2)O and subsequently catalyzed by in situ generated copper sulfide. The pure peptides were isolated in satisfactory yields in less than 5 minutes.

Mild, efficient and racemization-free synthesis of N-protected α, β-unsaturated γ-amino esters with unprecedented high E- stereoselectivity is described. This method is found to be compatible with Boc-, Fmoc- and other side chain protecting groups. The crystal conformations of the vinylogous γ-amino esters in monomers and in homo- and mixed dipeptides are studied. Further, the vinylogous homo-dipeptide showed a β-sheet conformation, while mixed α- and α,β-unsaturated γ-hybrid dipeptide adapted an irregular structure in single crystals.

Problem: Sperm flagellar protein 2 (SFP2), which was earlier identified using a novel combinatorial approach, was evaluated for its contraceptive potential in mice., Method of Study: Male mice were actively immunized with two synthetic peptides of SFP2. Antipeptide antibody was characterized by Western blot and indirect immunofluorescence. Immune response was monitored, and mating studies were performed 6 and 22 weeks post-immunization., Result: Antibodies to the SFP2 peptide 1 recognized a doublet at 220- to 230-kDa region only in the epididymal protein extract. Peptide 1 antibody recognized the cognate protein on spermatozoa from mouse, rat, and human. Histological analysis of testis and epididymis of the immunized mice indicated no deleterious effect. Incubation of sperm with the immune sera of peptide 1 caused significant reduction in motility and viability but did not agglutinate sperm. Only synthetic peptide 1 gave rise to high-level antibodies in all the immunized mice, which on mating resulted in reduced fertility rate (20%) when compared with PBS control animals (100%). The antibody levels in the immunized males declined by 22 weeks post-immunization, resulting in 100% reinstatement of fertility., Conclusion: These data provide an experimental basis for the development of effective contraceptive vaccine based on new epididymal target., (© 2011 John Wiley & Sons A/S.)

Coal coking, precious metals mining and nitrile polymer industries generate over several billion liters of cyanide-containing waste annually. Economic and environmental considerations make biological technologies attractive for treatment of wastes containing high organic content, in which the microbial cultures can remove concentrations of organics and cyanide simultaneously. For cyanide and phenol bearing waste treatment, an upflow anaerobic sludge blanket reactor has been developed, which successfully removed free cyanide 98% (with feed concentration of 20 mg 1(-1)) in presence of phenol. The effect of cyanide on phenol degradation was studied with varying concentrations of phenol as well as cyanide under anaerobic conditions. This study revealed that the methanogenic degradation of phenol can occur in the presence of cyanide concentration 30-38 mg 1(-1). Higher cyanide concentration inhibited the phenol degradation rate. The inhibition constant Ki was found to be 38 mg 1(-1) with phenol removal rate of 9.09 mg 1(-1.) x h.

A facile, efficient and racemization-free method for the synthesis of N-protected β-amino alcohols and peptaibols using N-hydroxysuccinimide active esters is described. Using this method, dipeptide, tripeptide and pentapeptide alcohols were isolated in high yields. The conformations in crystals of β-amino alcohol, dipeptide and tripeptide alcohols were analysed, with a well-defined type III β-turn being observed in the tripeptide alcohol crystals. This method is found to be compatible with Fmoc-, Boc- and other side-chain protecting groups.

A facile synthetic route for the preparation of N-protected γ-amino β-keto esters from amino aldehydes and ethyl diazoacetate is described. The two component coupling is facilitated by tin(II) chloride followed by semipinacol rearrangement leading to the product in quantitative yield. The reaction is mild, instantaneous and compatible with Boc-, Fmoc- and Cbz-amino protecting groups.

Functionally immature spermatozoa leave the testis mature during epididymal transit. This process of maturation involves either addition of new proteins or modification of existing proteins onto the sperm domains that are responsible for domain-specific functions. Epididymal proteins are preferred targets for immunocontraception. In an attempt to identify epididymis-specific sperm proteins, we used a novel combinatorial approach comprising subtractive immunization (SI) followed by proteomics. Following SI, sera of mice were used for immunoproteomics, which led to the identification of 30 proteins, of which four proteins namely sperm head protein 1, sperm flagella protein 2 (SFP2), SFP3, and SFP4 are being reported for the first time on sperm. Another group of four proteins namely collagen alpha-2 (I) chain precursor, homeodomain-interacting protein kinase 1, GTP-binding protein Rab1, and ubiquinol cytochrome c reductase core protein II although reported earlier in testis are being reported for the first time in epididymal sperm. Furthermore, seven out of these eight novel proteins could be validated using peptide ELISA. These data are a useful repository, which could be exploited to develop targets for post-testicular immunocontraception or biomarkers for infertility diagnosis and management.