Correlating antifungal Azole drug resistance and mis-sense mutations of ERG11 has been paradoxical in pathogenic yeast Candida albicans. Amino acid substitutions (single or multiple) are frequent on ERG11, a membrane bound enzyme of Ergosterol biosynthesis pathway. Presence or absence of mutations can not sufficiently predict susceptibility. To analyze role of mis-sense mutations on Azole resistance energetically optimized, structurally validated homology model of wild C.albicans ERG11 using eukaryotic template was generated. A Composite Search Approach is proposed to identify vital residues for interaction at 3D active site. Structural analysis of catalytic groove, dynamics of substrate access channels and proximity of Heme prosthetic group characterized ERG11 active site. Several mis-sense mutations of ERG11 reported in C.albicans clinical isolates were selected through a stringent criterion and modeled. ERG11 mutants subsequently subjected to a four tier comparative biophysical analysis. This study indicates (i) critical interactions occur with residues at anterior part of 3D catalytic groove and substitution of these vital residues alters local geometry causing considerable change in catalytic pocket dimension. (ii) Substitutions of vital residues lead to confirmed resistance in clinical isolates that may be resultant to changed geometry of catalytic pocket. (iii)These substitutions also impart significant energetic changes on C.albicans ERG11 and (iv) include detectable dynamic fluctuations on the mutants. (v)Mis-sense mutations on the vital residues of the active site and at the vicinity of Heme prosthetic group are less frequent compared to rest of the enzyme. This large scale mutational study can aid to characterize the mutants in clinical isolates.Electronic supplementary materialThe online version of this article (doi:10.1186/2193-1801-3-660) contains supplementary material, which is available to authorized users.

Tafazzin (EC 2.3.1.23) is a Phospholipid Transacylase involved in Cardiolipin remodeling on mitochondrial membrane and coded by TAZ gene (Cytogenetic Location: Xq28) in human. Its mutations cause Barth syndrome (MIM ID: #302060)/3-Methyl Glutaconyl Aciduria Type II, an inborn error of metabolism often leading to foetal or infantile fatality. Nevertheless, some mis-sense mutations result in mild clinical symptoms. To evaluate the rationale of mild symptoms and for an insight of Tafazzin active site, sequence based and structure based ramifications of wild and mutant Tafazzins were compared in-silico. Sequence based domain predictions, surface accessibilities on substitution & conserved catalytic sites with statistical drifts, as well as thermal stability changes for the mutations and the interaction analysis of Tafazzin were performed. Crystal structure of Tafazzin is not yet resolved experimentally, therefore 3D coordinates of Tafazzin and its mutants were spawned through homology modeling. Energetically minimized and structurally validated models were used for comparative docking simulations. We analyzed active site geometry of the models in addition to calculating overall substrate binding efficiencies for each of the enzyme-ligand complex deduced from binding energies instead of comparing only the docking scores. Also, individual binding energies of catalytic residues on conserved HX4D motif of Acyltransferase superfamily present in Tafazzins were estimated. This work elucidates the basis of mild symptoms in patients with mis-sense mutations, identifies the most pathogenic mutant among others in the study and also divulges the critical role of HX4D domain towards successful transacylation by Taffazin. The in-silico observations are in complete agreement with clinical findings reported for the patients with mutations.

This article has been removed: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal) This meeting abstract has been removed by the Publisher. Due to an administrative error, abstracts that were not presented at the ISDN 2014 meeting were inadvertently published in the meeting's abstract supplement. The Publisher apologizes to the authors and readers for this error.

Context: Up to 60% of patients with systemic lupus erythematosus develop lupus nephritis (LN). Tubulointerstitial nephritis (TIN) includes interstitial inflammation, tubulitis, tubular atrophy (TA), and interstitial fibrosis. These are considered independent risk factors for renal outcome. Aims: To evaluate the occurrence of TIN in LN and to correlate it with clinical and histopathological variables and renal outcome. Settings and Design: It was a prospective, single-center study. Subjects and Methods: One hundred and thirty-two LN cases were evaluated. Light microscopic scoring of interstitial inflammation, fibrosis, and TA was done as follows: 0 (nil); 1+ (mild - <25% of the area of observed cortex); 2+ (moderate - >25% to 50% of the area of observed cortex); 3+ (severe - >50% of the area of observed cortex). For direct immunofluorescence study, fluorescein isothiocyanate-conjugated polyclonal rabbit antisera against human IgG, IgA, IgM, C3c, C1q, kappa, and lambda antibodies (DAKO, Germany) were used. Statistical Analysis Used: Statistical software GraphPad Prism version 6.1. Results: Significant TIN was present in 6% of cases associated with high National Institutes of Health activity and chronicity indices irrespective of the modified International Society of Nephrology and Renal Pathology Society class of LN. In the cases where inflammation and fibrosis are marked, significantly raised serum creatinine, low estimated glomerular filtration rate, high 24-h urinary protein excretion, and reduced survival without any complete remission were seen. Severe interstitial and tubular inflammations without chronicity were also associated with low survival rate due to frequent relapse and significant hypertension. Conclusions: Activity and chronicity indices describing TIN components become essential to predict the survival, therapeutic response, and disease prognosis in LN.

Background: Lupus nephritis (LN) is the assemblage of glomerular, tubulointerstitial and vascular changes. Despite the fact that glomerular changes are overemphasized in pathological classification and scoring system, but the existence of vascular damage negatively impact the clinical course. Aims and Objective: This study was conducted to determine the clinicopathological spectrum of renal vascular lesions in lupus nephritis. Materials and Methods: Renal microvascular lesions in biopsy proven lupus nephritis were classified into 5 major categories-thrombotic microangiopathy, true vasculitis; lupus vasculopathy, uncomplicated vascular immune deposits, and arterial. Clinical details, laboratory parameters and histopathological variables were compared among all groups. Summary of chronic changes was also assessed. Results: Biopsies from 56 patients revealed thrombotic microangiopathy (2), lupus vasculopathy (3), uncomplicated vascular immune deposit (6), PAN type vasculitis (1) and arterial sclerosis (13). No renal vascular lesions were found in 35.18% of patients. At the time of biopsy, arterial sclerosis or lupus vasculopathy patients were older Nephritis subtype. Activity indices were higher in lupus vasculopathy group whereas patients with arteriosclerosis showed highest chronicity index. Conclusions: Renal vascular lesions are common in systemic lupus erythematosus patients with nephritis and may be associated with aggressive clinical course.