Session 8
Comm unications
Newfrontiers inbiotechnological applications of yeasts Yeast to enhance winesafety
and heaIthinessA.Caridi,R.Sidari
S.ezionedi Microbiologia, Dipartimento diScienze eTecnologie
Agro-Forestali eAmbientali -DISTA FA,Facoltà diAgraria, Università degliStudi"Mediterranea" diReggio Calabria
Today, the consumer is extremely health mindful and
searches for foods and beverages having helpful
biological properties, such as high contents in antioxidant substances and low content in toxic compounds. Scientific research in the last years has proposed a lot of way to enhance safety and healthiness of wines, demonstrating that various factors may
positively influence them. For example, notable correlations between yeast used for winemaking and phenolic compounds in wine were reported,
demonstrating that strain behaviour can somewhat modify chromatic properties, phenolic profile and
antioxidant power of wine. The present contribution aims to stress the role ofthe microbial starter selection in this perspective, paying also attention to the new genomic strategies helpful to improve specific tr~its of the selected microbial starters. The final target IS the production of wines exhibiting high levels of healthy cornpounds, for example resveratrol, and low levels of toxic compounds, such as sulphur dioxide, acetaldehyde, methanol, ethyl carbamate, biogenic amines, medium-chain fatty acids, ochratoxin A,
pesticides, fungicides, and heavy metals.
References:
CaridiA Sidari R- Safety and healthiness enhancement ofred wines by select~dmicrobial starters. In:RedWineand Health, Editor:PauI O.Byrne,Nova SciencePublishers, lnc.,7,205-233, 2009.
Acomparative expression analysis of a thermophilic putative lipase in mesophilic
hosts
O.Lòpez-Lopez', P.FuciiioS2. L.M.Pastrana/. M.L.Rùa'.
M.E. Cerdan', M.l. Gonzàlez Siso'
'Molecular and Cellular BiologyDepartment. SciencesFaculty. University
or
A Coruiìa. Campus daZapateira, sin 15071.A Coruna.SPAIN
2Analytical andFoodChemistry Departarnent. UniversiryofVigo Campus Ourense.As Lagoas.32004 Ourense.SPAIN
Lipases and esterases are the most widely biocatalysts
used in industry. Thermophilic enzymes are of special interest due to their high robustness. Obtaining these
proteins from their natural sources isoften challenging given the low growing rates or thermophiles and ~he
high temperature required for the cultures. Developing
heteroloaous overexpression systems in mesophilic
hosts is ~an alternative that can be used in order lO achieve a large-scale production of low-cost therrnophilic biocatalysts.
For heterologous expression of proteins, Saccharomyces cerevisiae and K/uyveromyces factis
are species extensively studied as hosts among the yeasts, whereas Escherichia coli isthe most cornmonly
used as bacterial host. E. coli tends to be the first
choice to produce recombinant proteins from bacterial
sources. However, not always a successful expression of the target proteins is achieved. Overexpressed proteins are often accumulated as insoluble forms
(inclusion bodies). Then, the alternative or expression inyeasts should bealso approached.
In this work. the heterologous expression ofthe gene of aputative lipase from Thermus thermophilus 1-IB27 (yp_005592.\) was analyzed to compare the suitability of different mesophilic hosts and heterologous
expression systerns.