Lignocellulosic feedstocks are thought to have great economic and environmental significance for future biotechnological production processes. For cost-effective and efficient industrial processes, complete and fast conversion of all sugars derived from these feedstocks is required. Hence, simultaneous or fast sequential fermentation of sugars would greatly contribute to the efficiency of production processes. One of the main challenges emerging from the use of lignocellulosics for the production of ethanol by the yeast Saccharomyces cerevisiae is efficient fermentation of D-xylose and L-arabinose, as these sugars cannot be used by natural S. cerevisiae strains. In this study, we describe the first engineered S. cerevisiae strain (strain IMS0003) capable of fermenting mixtures of glucose, xylose, and arabinose with a high ethanol yield (0.43 g g ؊1 of total sugar) without formation of the side products xylitol and arabinitol. The kinetics of anaerobic fermentation of glucose-xylose-arabinose mixtures were greatly improved by using a novel evolutionary engineering strategy. This strategy included a regimen consisting of repeated batch cultivation with repeated cycles of consecutive growth in three media with different compositions (glucose, xylose, and arabinose; xylose and arabinose; and only arabinose) and allowed rapid selection of an evolved strain (IMS0010) exhibiting improved specific rates of consumption of xylose and arabinose. This evolution strategy resulted in a 40% reduction in the time required to completely ferment a mixture containing 30 g liter ؊1 glucose, 15 g liter ؊1 xylose, and 15 g liter ؊1arabinose.In recent years, the need for biotechnological manufacturing based on lignocellulosic feedstocks has become evident (6, 10). In contrast to the readily fermentable, mainly starch-or sucrose-containing feedstocks used in current biotechnological production processes, lignocellulosic biomass requires intensive pretreatment and hydrolysis, which yield complex mixtures of sugars (3,7,14,27). For cost-effective and efficient industrial processes, complete and fast conversion of all sugars present in lignocellulosic hydrolysates is a prerequisite. The major hurdles encountered in implementing these production processes are the conversion of substrates that cannot be utilized by the organism of choice and, even more importantly, the subsequent improvement of sugar conversion rates and product yields.The use of evolutionary engineering has proven to be very valuable for obtaining phenotypes of (industrial) microorganisms with improved properties, such as an expanded substrate range, increased stress tolerance, and efficient substrate utilization (16,17). Also, for the yeast Saccharomyces cerevisiae, the preferred organism for large-scale ethanol production for the past few decades, evolutionary engineering has been extensively used to select for industrially relevant phenotypes. For ethanol production from lignocellulose by S. cerevisiae, one of the main challenges is efficient conversion of the pentoses ...

BackgroundNAD (P) H: quinone oxidoreductase 1 (NQO1) is a xenobiotic metabolizing enzyme that detoxifies chemical stressors and antioxidants, providing cytoprotection in normal tissues. However, high-level expression of NQO1 has been correlated with numerous human malignancies, suggesting a role in carcinogenesis and tumor progression. This study aimed to explore the clinicopathological significance of NQO1 and as a prognostic determinant in breast cancer.MethodsA total of 176 breast cancer patients with strict follow-up, 45 ductal carcinoma in situ (DCIS), 22 hyperplasia and 52 adjacent non-tumor breast tissues were selected for immunohistochemical staining of NQO1 protein. Immunofluorescence staining was also performed to detect the subcellular localization of NQO1 protein in MCF-7 breast cancer cells. Eight fresh breast cancers paired with adjacent non-tumor tissues were quantified using real time RT-PCR (qRT-PCR) and western blot. The correlations between NQO1 overexpression and the clinical features of breast cancer were evaluated using chi-square test and Fisher’s exact tests. The survival rate was calculated using the Kaplan–Meier method, and the relationship between prognostic factors and patient survival was also analyzed by the Cox proportional hazards models.ResultsNQO1 protein showed a mainly cytoplasmic staining pattern in breast cancer. The strongly positive rate of NQO1 protein was 61.9% (109/176) in breast cancer, and was significantly higher than in DCIS (31.1%, 14/45), hyperplasia tissues (13.6%, 3/22) and adjacent non-tumor tissues (13.5%, 7/52). High-level expression of NQO1 protein was correlated with late clinical stage, poor differentiation, lymph node metastasis, Her2 expression and disease-free and 10-year overall survival rates in breast cancer. Moreover, multivariate analysis suggested that NQO1 emerged as a significant independent prognostic factor along with clinical stage and Her2 expression status in patients with breast cancer.ConclusionsHigh-level expression of NQO1 appears to be associated with breast cancer progression, and may be a potential biomarker for poor prognostic evaluation of breast cancers.

The purpose of the present paper was to investigate the significance of DEK protein expression in uterine cervical lesions and its relationship with HPV infection status. DEK protein expression was studied in 253 cervical lesions, including 30 non-neoplastic cervix with or without squamous metaplasia, 64 cervical intra-epithelial neoplasias (CIN; CIN-1, n = 28; CIN-2, n = 17; CIN-3, n = 19), 102 squamous cell carcinomas (SCC), 51 adenocarcinomas, and six adenosquamous cell carcinomas (adenoSCC) on immunohistochemistry. For comparison, HPV-positive and -negative cervical cancer cell lines were also included. The HPV screening was performed using TaKaRa polymerase chain reaction. On immunohistochemistry DEK was found to be negative in all 30 non-neoplastic cervical epithelia, but it was positive in 96.1% of SCC (98/102), 92.2% of adenocarcinomas (47/51), 100% of adenoSCC (6/6), 85.7% of CIN-1 (24/28), 94.1% of CIN-2 (16/17), and 89.5% of CIN-3 (17/19). There was no significant difference between HPV-positive and -negative cervical lesions. Also, strongly positive staining was observed in all aforementioned cervical cancer cell lines regardless of HPV infection, according to immunocytochemistry. In summary, DEK plays an important role in the carcinogenesis of cervical cancers, and can be helpful for early diagnosis, and is a potential therapeutic target.

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