Week 1

Its now two weeks since we arrived in Marbury which is a pretty city snuggled in the Lahn valley. We are staying in an apartment at the University Guest house, which is on the Eastern side of the valley. There are other university/institute visitors and post docs staying here. Its quite basic but fulfills all our needs as its warm, has a good hot shower and is clean. Downside is the poor internet service. It has been a good time to arrive in Marburg as it has just started to warm up after a prolonged grey/bleak winter. When we arrived last week the trees were all quite bare but within a few days all the buds have burst so all the trees are now green with leaf. It also coincided with the start of the spring/summer semester for students so the town is busy with students. On the warm days they can be found having BBQs and drinking beer on the banks of the Lahn – students are the same everywhere! It is a 25 min walk up through the forest to the Max Planck University and science departments associated with Philipps University. I think most of the arts and commerce faculties are located downtown. This walk is a pleasant way to start the day.

The Institute itself has wonderful facilities. I have a large office to myself, which is good for reading and writing. This last week I attended an Institute Seminar on bacterial motility, a Department seminar from post doc Pierre Grognet, a journal club and then on Friday the weekly round table lab meeting involving short verbal presentations by the different groups on their results for the last week – no powerpoint but muffins and coffee. Last week I met with post docs Pierre Grognet and Libera Lo Presti.

Pierre is investigating how Um (Ustilago maydis) senses the host leaf surface during infection. Previous work showed that Um senses both hydrophobicity and hydroxy fatty acids (cutin monomers/oxylipins). Sensing of hydrophobicity is through Msb2, a mucin, and Sho1, with transduction of the signal through the pheromone MAP kinase pathway. However, nothing is known about the sensing of HFAs. He gave a talk on this work in the volatiles session at Asilomar (see concurrent sessions and poster #556), which some of you may have attended.

Libera is developing the biotin tag assay for effectors and gave a talk on this work in the Effector Biology session at Asilomar. The strategy is to tag the effector with a Biotag (small peptide) that serves as a substrate for BirA, the bacterial biotin ligase. If the effector is translocated into a plant cell transgenic for the expression of BirA then it will become biotinylated and can be picked up after IP and Mass Spec. However, as elegant as this assay sounds its much more difficult than you would imagine – which highlights once again the challenges on unambiguously demonstrating effector transport into the plant cell cytoplasm. The gold standard remains TEM of immunogold labeled cells using antibody to the effector. A useful control is to use the split GFP system as described in Nature Biotechnology (2005) 23: 102-107. This relies on tagging the effector with a very short N-terminal component of GFP (C11), which can bind to the longer C-terminal component (C10), as in BiFC, to form a functional GFP.  For the system to work well it is important there is no damage to the host tissue through stress or other means as this will lead to leakage of the proteins from one compartment into the next. 

On Thursday Christine and I bought bicycles from a bike tour company downtown so we are now mobile! But we are living up a very steep hill so still need to find a better way down into the valley. Yesterday we tried them out with a 25 km ride down the Lahn and through some lovely little villages including Argenstein, Roth, Niederwalgern, Niederweimar, Gisselberg then back to Marburg after which we had very sore backsides. Last evening we went to hear the Marburg symphony orchestra play some Mozart in Elisabethkirch, a beautiful 13^th century Gothic church that holds the tomb of St Elizabeth of Hungary. It is one of the landmarks of the city, together with Landgraves castle (Landgrafenschloss), the old university and the town hall (Rathus), which has some beautiful old paintings.

On Sunday we walked the Behring trail a 5 km walk that celebrates the life of Emil Behring who received the Nobel Prize in 1901 for the development of vaccines for diphtheria and tetanus. There is a magnificent Mausoleum in the forest where he is buried. The manufacturing site today is a series of at least 20 buildings nestled in a valley within the forest an opening to the outskirts of Marburg.