Determination of thioxylo-oligosaccharide binding
to family 11 xylanases using electrospray ionization
Fourier transform ion cyclotron resonance mass
spectrometry and X-ray crystallography
Janne Ja
¨
nis
1
, Johanna Hakanpa
¨
a
¨
1
, Nina Hakulinen
1
, Farid M. Ibatullin
2
, Antuan Hoxha
3
,
Peter J. Derrick
3
, Juha Rouvinen
1
and Pirjo Vainiotalo
1
1 Department of Chemistry, University of Joensuu, Finland
2 Biophysics Division, Petersburg Nuclear Physics Institute, Gatchina, Russia
3 Department of Chemistry, Mass Spectrometry Institute, University of Warwick, Coventry, UK
Glycoside hydrolases [1] are ubiquitous enzymes
involved in biochemical degradation of cellulose and
hemicellulose, the main constituents of plant cell walls.
They cleave the glycosidic linkages between pyranose
or furanose rings of disaccharides, oligosaccharides
and polysaccharides. Glycoside hydrolases can be clas-
sified on the basis of their substrate specificity, mech-
anism of action, or amino-acid sequence [2–5]. To
Keywords
Fourier transform ion cyclotron resonance
(FT-ICR); noncovalent binding; thioxylo-
oligosaccharides; X-ray crystallography;
xylanases
Correspondence
P. Vainiotalo, Department of Chemistry,
University of Joensuu, PO Box 111,
FI-80101 Joensuu, Finland
Fax: +358 13 2513360
Tel: +358 13 2513362
E-mail: pirjo.vainiotalo@joensuu.fi
(Received 4 January 2005, revised 1 March
2005, accepted 10 March 2005)
doi:10.1111/j.1742-4658.2005.04659.x
Noncovalent binding of thioxylo-oligosaccharide inhibitors, methyl 4-thio-
a-xylobioside (S-Xyl2-Me), methyl 4,4
II
-dithio-a-xylotrioside (S-Xyl3-Me),
methyl 4,4
II
,4
III
-trithio-a-xylotetroside (S-Xyl4-Me), and methyl 4,4
II
,
4
III
,4
IV
-tetrathio-a-xylopentoside (S-Xyl5-Me), to three family 11 endo-1,4-
b-xylanases from Trichoderma reesei (TRX I and TRX II) and Chaetomium
thermophilum (CTX) was characterized using electrospray ionization
Fourier transform ion cyclotron resonance (FT-ICR) MS and X-ray crys-
tallography. Ultra-high mass-resolving power and mass accuracy inherent
to FT-ICR allowed mass measurements for noncovalent complexes to
within |DM|
average
of 2 p.p.m. The binding constants determined by MS
titration experiments were in the range 10
4
)10
3
M
)1
, decreasing in the
series of S-Xyl5-Me ‡ S-Xyl4-Me > S-Xyl3-Me. In contrast, S-Xyl2-Me
did not bind to any xylanase at the initial concentration of 5–200 lm, indi-
cating increasing affinity with increasing number of xylopyranosyl units,
with a minimum requirement of three. The crystal structures of CTX–
inhibitor complexes gave interesting insights into the binding. Surprisingly,
none of the inhibitors occupied any of the aglycone subsites of the active
site. The binding to only the glycone subsites is nonproductive for catalysis,
and yet this has also been observed for other family 11 xylanases in com-
plex with b-d-xylotetraose [Wakarchuk WW, Campbell RL, Sung WL,
Davoodi J & Makoto Y (1994) Protein Sci 3, 465–475, and Sabini E,
Wilson KS, Danielsen S, Schu
¨
lein M & Davies GJ (2001) Acta Crystallogr
D57, 1344–1347]. Therefore, the role of the aglycone subsites remains con-
troversial despite their obvious contribution to catalysis.
Abbreviations
CTX, catalytic domain of Chaetomium thermophilum xylanase; ESI, electrospray ionization; FT-ICR, Fourier transform ion cyclotron
resonance; GlcNAc, N-acetyl-
D-glucosamine; Hex, hexose (Man ⁄ Gal); S-Xyl2-Me, methyl 4-thio-a-xylobioside; S-Xyl3-Me, methyl TransformdespairintodeterminationTransformdespairintodetermination Bởi: Joe Tye “Optimism can be sparked by leaders who reframe disastrous events in positive, empowering ways.” Dennis N.T Perkins: Leading at the Edge: Leadership Lessons from the Extraordinary Saga of Shackelton’s Antarctic Expedition Prevention is the best defense, but when despair strikes anyway, the best strategy is to transform it into the energy for determination Many very successful, very creative people have stood on despair’s doorstep, perhaps for a very long time, and returned more determined to become the person they were truly meant to be and to pursue their most authentic dreams Og Mandino, Buckminster Fuller, Billy Joel, Harold Hughes, and Robert Fulghum are among those who were actually on the brink of suicide when they turned around and realized that they had important work remaining to be done As Robert Fulghum wrote about his experience: “Death isn’t what I wanted It wasn’t less life, but more life – life with meaning” (emphasis in original) Great leaders recognize that despair is an emotional wasteland, and are quick to transform it intodetermination by investing the situation with meaning and with commitment to prevail against all odds When Ernest Shackleton’s ship Endurance was first trapped in and then crushed by Antarctic ice in 1916, one of his most daunting challenges was to maintain the morale of his twenty-eight crew members during their 634-day ordeal In Leading at the Edge, leadership consultant Dennis N.T Perkins and his co-authors describe some of the strategies that Shackleton used to hold his team together and bring them all home alive: Shackleton kept his men busy, knowing that idleness can foster a sense of lost control, which in turn leads to despair He was quick to defuse conflict, and used every excuse to hold a party or celebration of some sort 1/2 Transformdespairintodetermination He made sure his men understood that he had no doubt whatsoever they would all survive, and set a personal example of courage and self-sacrifice in doing the things that were necessary for that to occur He encouraged creative thinking to solve what appeared to be intractable problems, and when inaction would have been a fatal choice, he was willing to take what otherwise would have seemed unthinkable risks Shackleton knew that a leader’s first duty during tough times is to maintain hope and optimism, and to stave off despair, no matter how desperate the situation might seem In retrospect, one can speculate on how frequently members of the crew were tempted to quit before the breakthrough that led to their rescue Shackleton himself later wrote: “I have marveled often at the thin line that divides success from failure and the sudden turn that leads from apparently certain disaster to comparative safety.” 2/2 Page | 1 With Free Giveaway Rights Page | 2 22 Powerful Tools to Transform Your Fear Into Happiness, Peace and Inspiration Fear is undoubtedly one of the strongest and most influential emotional responses we have, and it can act as both a protective and destructive force depending on the situation. Obviously, fear can help us avoid dangerous situations, triggering the ―fight or flight‖ response when we feel threatened. Unfortunately, this same response can also be triggered when no real threat exists. We simply find ourselves feeling overwhelmed and anxious even when we know logically that no harm will come to us. For many of us, fear can become a serious hindrance in our lives, preventing us from getting a better job, meeting eligible life partners, seeking medical care, or even venturing outside our homes in severe cases. Fear is one of the most common reasons that people hold back on living the life of their dreams. Even if they intensely want to create better circumstances, they may struggle with an overwhelming fear of failure, so they refuse to take risks because they may have to endure unpleasant outcomes. In these cases the risk of failure seems to outweigh the benefits of success, so they hold back and do nothing. Fear of success can be a powerful hindrance as well, making people feel stressed and overwhelmed with the added responsibilities that would probably come with greater success. They may fear not being able to handle those responsibilities, or worry that they‘d feel pressured to keep attaining the same level of success in the future. These fears are often enough to cause people to sabotage their own efforts, even when they sincerely want to become more successful. Either way, fear is strong enough to paralyze most of us – whether the things we fear are real or imagined. Fear and Love Cannot Co-Exist By nature, fear and love act in conflicting ways in our lives. Fear is restrictive, repressive and limiting. Love is expressive, abundant and free-flowing. Fear contracts, love expands. Fear retreats, love forges new pathways. Fear is closed off and stagnant, love is open and vibrant. Because of the reflective nature of our universe, the mindset you most often hold will be mirrored in your every experience and in every person you encounter. When you live your life from a mindset of fear, you are bound to see that same quality of stagnation and repression everywhere. Your opportunities will seem smaller or more restrictive Page | 3 (or even non-existent). The people you interact with daily will probably seem more reserved, less generous, and less caring. Even your work will seem repressed, perhaps boring or unfulfilling; and your income may shrink in proportion too. On the other hand, when you begin living your life from a mindset of love, everything around you seems effusive and joyful. The people you meet seem warmer, kinder and jovial. Opportunities come rushing forth to meet YOU, rather than you having to chase after them, and your work will probably seem more fulfilling and enjoyable – not to mention more profitable. Contrary to popular belief, you do not need to be highly spiritual or ―enlightened‖ to live from love rather than fear. All it takes is a simple shift in mindset to create big changes in your outer world. The following article shares a very simple and effective way to shift from fear to love instantaneously: Worry and Love Cannot Occupy the Same Space The Three Universal Fears In his book, The Divine Matrix author Gregg Braden writes, “The root of our „negative‟ experiences may be reduced to one of three universal fears (or a combination of them): abandonment, low self-worth, or lack of trust.” When you think about it, all of the fearful responses you have in life probably correspond to one or more of these three universal fears. You may fear being alone, being rejected, or not being good TOPIC 06 – PASSIVE VOICE I. Transform the sentences into passive voice 1. Hurricanes destroy a great deal of property each year. 2. The committee is considering several new proposals. 3. The company has ordered some new equipment. 4. The manager should sign these contracts today. II. Use the correct form of verbs: 1. I am very happy (accept) to work in the company 2. She comes to my house to congratulate me on (invite) to a big company 3. Something needs (do) to solve the problem III. Special passive voice with MADE: 1. to be made of: Được làm bằng (Đề cập đến chất liệu làm nên vật) This table is made of wood 2. to be made from: Được làm ra từ (đề cập đến việc nguyên vật liệu bị biến đổi khỏi trạng thái ban đầu để làm nên vật) Paper is made from wood 3. to be made out of: Được làm bằng (đề cập đến quá trình làm ra vật) This cake was made out of flour, butter, sugar, eggs and milk. 4. to be made with: Được làm với (đề cập đến chỉ một trong số nhiều chất liệu làm nên vật) This soup tastes good because it was made with a lot of spices. IV. Special passive voice with HAVE, GET and NEED 1. Have something done a) Yesterday, (I / cut / my hair). b) Every Friday, (Joe / wash / his car). c) Tomorrow, (she / repair / her shower). d) Each Saturday, (we / deliver / a pizza) to our home. e) Last year, (Bob / clean / his house) by a charwoman. f) As Phil had a broken arm, (he / type / his texts) by his secretary. g) (I / pick up / the goods) tomorrow in the afternoon. 2. Need doing something/ need to be done V. Special passive voice 1. They said that Mary loved Tim 2. People believe that he is a good teacher 3. They say that she ate 10 eggs a day 5 tips to transform your idea into a real business Ideas are great, some people have the ability to think about new ways and new things that can change peoples' lives, enhance specific business needs or create a brand new industry www.acclux.com The only way to make an idea survives is to transform it into a real successful business that can generate money for you and for the idea itself, so it can evolve to something bigger If you have an idea and you are ready to follow your passion and dreams, you can get some inspiration and help from these tips www.acclux.com www.acclux.com Problem to solve The most important thing about your idea, what the idea is going to solve and what's the need that it is going to fulfill Why people will need your product or service? Being unique in what you are doing will guarantee your fast growth and business success 2 www.acclux.com Understand your market and your competitors You need to understand your market and determine your potential competitors, what they are doing and how you can differentiate yourself from the others 3 www.acclux.com Business is about automation To have a real business, you need to automate your processes from day one Your sales cycle automation is essential to build a successful business model; your cash flow management, invoices and payment automation must be done from the very beginning You can start with cloud business software that designed for startup business www.acclux.com www.acclux.com Start the first step Planning is great, but it must be translated into actions, start your ride and don't wait too much, it requires a lot of passion, energy and patience to complete this road successfully Rent a place for your office or start from your home with a real dedication to a certain place to be working from www.acclux.com www.acclux.com Get a feedback and be flexible to make changes Try to get a real feedback from trusted people, be open minded to hear other opinions and be flexible to make changes to your business model It will be easier to make changes now than later www.acclux.com & Final Tip www.acclux.com Don't give up Your commitment is the key to success Starting a business is an interesting road to take and it's challenging at the same time It requires hard work, patient and most of all commitment www.acclux.com Thank you! acclux.com [...]...Planning is great, but it must be translated into actions, start your ride and don't wait too much, it requires a lot of passion, energy and patience to complete this road successfully Rent a place for your office or start from your home with a real dedication to a certain place to be working from www.acclux.com 5 www.acclux.com Get a feedback and be flexible to make changes Try to get a real feedback... minded to hear other opinions and be flexible to make changes to your business model It will be easier to make changes now than later www.acclux.com & Final Tip www.acclux.com Don't give up Your commitment is the key to success Starting a business is an interesting road to take and it's challenging at the same time It requires hard work, patient and most of all commitment www.acclux.com Thank you! acclux.comBefore&After BAmagazine.com ® i U X How to look real Set the stage with authentic visual cues Continued Continued How to look real 0617 Before&After BAmagazine.com ® i U X How to look real Before designing, check out the party! Here’s how to transform a dull layout into an energetic expression of the real event Before The Kentucky Mine Summer Concert Series in the Sierra Nevada mountains is low-budget entertainment under the stars From a small stage beneath 150-foot pines, the rousing sounds of bluegrass, balladeers and folk singers mingle with the sweet fragrance of summer in the forest It’s a great time Problem is, the Web banner promoting all this conveys none of it It’s well-crafted and tidy (right), but that’s what’s wrong Its neat lines and smooth surfaces project no energy, no musicality and no sense of place That’s because the designer was thinking layout and missed the event Here’s how to get all of that good stuff in KENTUCKY MINE AMPHITHEATER SUMMER CONCERT SERIES Foot stompin’ fun! Every Friday, p.m July thru August Where’s the party? The black hat hints at the country-western theme of the summer concerts, but nothing’s happening; the lines are too straight, the type is too static and the space is too empty to convey the rollicking, banjo-twanging, foot-stomping energy of the real thing of 11 How to look real 0617 Before&After ® How to look real of 11 BAmagazine.com i U X It was designed “by the book” The designer of this ad was unfamiliar with the event and so made a common mistake— he designed from his imagination Such results will almost always look artificial Reversed type is inauthentic Old printing was always dark on light Before KENTUCKY MINE AMPHITHEATER SUMMER CONCERT SERIES Foot stompin’ fun! Every Friday, p.m July thru August Inauthentic elements • Positive-negative color fields KENTUCKY MINE AMPHI• Straight edges and sharp corners • Contemporary color palette SUM- Sleek and smooth country? The “before” is crafted well enough It has a focal point, harmonious colors, consistent use of type, and things are neatly aligned But the result is lifeless That’s because it doesn’t express the subject Smooth surfaces and straight lines, for example, are elements of urban boardrooms (left), not the mountain outdoors (above) The banner mixes other visual signals: • Color fields are flat and smooth • Top bar is mechanical, and its type is reversed • Color palette is made up, not based on the real scene • The real outdoors has rocks, trees, wooden buildings, wagon wheels and dirt, all gritty, weathered and rough • Old-West printing had no fancy reverses • Old paper has color and texture of 11 How to look real 0617 Before&After ® How to look real BAmagazine.com of 11 i U X The type is static, and the space is too passive Usherwood Black has designed-in quirks, but the effect looks polished and synthetic The black hat has no owner, and music is nowhere in sight Before KENTUCKY MINE AMPHITHEATER SUMMER CONCERT SERIES Foot stompin’ fun! Every Friday, p.m July thru August Where’s the music? The hat is the focal point, and the “read breeze”—our natural left-to-right drift across a page— reinforces its position (the eye moves towards it), but it’s a passive image that conveys neither forest nor music nor party The result is a disconnect between image and message Dips SUMMER Half serifs Cupped feet Smooth edges Full serifs (Above) Quirky ITC Usherwood Black is an appealing type choice for several reasons, one of which are the unique half serifs on its M’s and N’s Although its characters are full of the irregularities one might see in old, wooden type, the edges are sharp and its overall line strong and uniform The result: Usherwood looks designed and not authentically old of 11 How to look real 0617 Before&After ® How to look real BAmagazine.com of 11 i U X It’s time to start over To convey the real event, we need authentic visual cues —real objects, real colors, real textures And because it’s a party, we need .. .Transform despair into determination He made sure his men understood that he had no doubt whatsoever they would... that a leader’s first duty during tough times is to maintain hope and optimism, and to stave off despair, no matter how desperate the situation might seem In retrospect, one can speculate on how