Characterization of amino acids in silk sericin protein from Gonometa rufobrunnae by MEKC with phenyl isothiocyanate derivatization

An MEKC method was developed for the separation and characterization of phenyl-isothiocyanate (PITC)-labeled amino acids derived from Gonometa rufobrunnae silkworm after microdialysis sample cleanup. The influence of the buffer and SDS concentration on the resolution of the amino acids was investigated. A buffer system consisting of 25 mM phosphate, 10 mM borate buffer at pH 9.00, and 70 mM SDS showed the best results, with 13 PITC-amino acid derivatives being resolved out of 15 possible amino acids that were under study. Microdialysis sampling demonstrated its efficiency as a sample cleanup technique. Sericin protein from G. rufobrunnae was found to be characterized by at least 11 positively identified amino acids. These included His, Tyr, Ser, Ala, Phe, Lys, Gly, Arg, Cys, Glu, and Asp. Leu/Met and Val/Thr were coeluting pairs and hence could not be positively confirmed.     

Synthesis and screening of libraries of synthetic tripodal receptor molecules with three different amino acid or peptide arms: identification of iron binders

A novel selectively deprotectable triazacyclophane scaffold was used for the design and split-mix synthesis of two libraries of solid-phase bound tripodal synthetic receptors possessing three different amino acid or peptidic arms. In the synthesis of the first library, the two outer arms consisted of amino acid Ala, Arg, Asp, Gln, Gly, Lys, Phe, Ser, Tyr, or Val and the middle arm consisted of amino acid Asn, Glu, His, Leu, or Pro. The second library contained amino acid and/or (di)peptide arms. The arms were different in all library members. The first outer arm consisted of amino acid(s) Ala, Arg, Gln, Phe, or Ser, the second outer arm consisted of amino acid(s) Asp, Gly, Lys, Tyr, or Val, and the middle arm consisted of amino acid(s) Asn, Glu, His, Leu, or Pro, leading to a 27 000 member library of synthetic tripodal receptor molecules. In on-bead screening experiments, a remarkable selectivity of some library members for Fe(3+) was observed and decoding of their structures by Edman degradation revealed consensus sequences with structural resemblance to non-heme iron proteins.     

磷酸三乙胺-乙腈流动相体系反相分离2，4-二硝基氟苯-氨基酸衍生物

从两个方面改进了反相分离2,4-二硝基氟苯-氨基酸衍生物测定氨基酸的分析方法:一是使用高缓冲容量pH 2.75和6.50的磷酸三乙胺-乙腈流动相体系代替醋酸盐/乙腈流动相体系;另一个是强调了衍生反应的操作细节。以含精、丝、天冬、谷、苏、甘、丙、脯、组、蛋、缬、色、苯丙、亮、异亮、赖、酪氨酸注射液为目标试样,对方法进行认证,线性不低于0.9999(对谷氨酸、赖氨酸和酪氨酸不低于0.9998),准确度（回收率）为100±1%,精密度（RSD）低于0.5%,均优于以往的方法。方法适用于在一般液相色谱实验室进行氨基酸注射液和原料药的分析,无需专用氨基酸分析仪。     

Electron capture dissociation product ion abundances at the X amino acid in RAAAA-X-AAAAK peptides correlate with amino acid polarity and radical stability

We present mechanistic studies aimed at improving the understanding of the product ion formation rules in electron capture dissociation (ECD) of peptides and proteins in Fourier transform ion cyclotron resonance mass spectrometry. In particular, we attempted to quantify the recently reported general correlation of ECD product ion abundance (PIA) with amino acid hydrophobicity. The results obtained on a series of model H-RAAAAXAAAAK-OH peptides confirm a direct correlation of ECD PIA with X amino acid hydrophobicity and polarity. The correlation factor (R) exceeds 0.9 for 12 amino acids (Ile, Val, His, Asn, Asp, Glu, Gln, Ser, Thr, Gly, Cys, and Ala). The deviation of ECD PIA for seven outliers (Pro is not taken into consideration) is explained by their specific radical stabilization properties (Phe, Trp, Tyr, Met, and Leu) and amino acid basicity (Lys, Arg). Phosphorylation of Ser, Thr, and Tyr decreases the efficiency of ECD around phosphorylated residues, as expected. The systematic arrangement of amino acids reported here indicates a possible route toward development of a predictive model for quantitative electron capture/transfer dissociation tandem mass spectrometry, with possible applications in proteomics.     

Trypsin inhibiting material from Ascaris lumbricoides var. suum. I. Preparation of pure trypsin inhibitors

The purification of a trypsin inhibitor from Ascaris lumbricoides var. suum is described. The electrophoretically pure preparation which inhibits trypsin in a specific manner is a relatively small peptide containing 5 Asp, 4 Thr, 1 Ser, 11 Glu, 6 Pro, 6 Gly, 5 Ala, 2 Val, 10 (Cys)_1/2, 3 Ile, 2 Phe, 7 Lys, 3 Arg and 1 Try.     

大亚湾沉积物中氨基酸的垂直分布——沉积物柱样W0中的水解氨基酸

测定了采自大亚湾近岸海域的一个长60cm的沉积物柱样W0中15种水解氨基酸的含量；结果表明，15种水解氨基酸含量均随深度而下降，其中苏氨酸、丝氨酸、甘氨酸、丙氨酸、精氨酸、缬氨酸、苯丙氨酸、亮氨酸、异亮氨酸的含量以及水解氨基酸总量随深度的变化可用指数方程c＝c0e^-kx加以描述；天冬氨酸、谷氨酸、丝氨酸、甘氨酸、丙氨酸和缬氨酸是大亚湾沉积物中最丰富的氨基酸。     

Translational diffusion constants of the amino acids: measurement by NMR and their use in modeling the transport of peptides

In this work, the translational self-diffusion constants, DT's, of 12 amino acids (Ala, Arg, Asn, Asp, Cys, Glu, His, Ile, Lys, Met, Phe, and Ser) are measured by field gradient NMR and extrapolated to infinite dilution. The experiments were carried out in D2O at 298 K at pD approximately =3.5 in 50 mM sodium phosphate buffer. Of these 12 amino acids, 6 are being reported for the first time (Asp, Cys, Glu, His, Lys, and Met) and the remaining 6 (Ala, Arg, Asn, Ile, Phe, and Ser) are compared with DT's from the literature. When corrected for differences in solvent viscosity and temperature, the discrepancy between DT's measured in the present work and those reported previously is always <8%, which is reasonable given the range of values reported previously by different groups. With the present work, DT's for all of the amino acids are now available. These diffusion constants are then used in modeling studies of the diffusion and free solution electrophoretic mobility, mu, of several model peptides. For this set of peptides, it is shown that modeling using revised input parameters results in improved agreement between model and experimental mobilities.     

MC1R Gene Polymorphism Affects Skin Color and Phenotypic Features Related to Sun Sensitivity in a Population of French Adult Women

The melanocortin-1 receptor ( MC1R ) gene is known to play a major role in skin and hair pigmentation and to be highly polymorphic in Caucasians. This study was performed to investigate the relationships between MC1R gene polymorphisms and skin color in a large sample of French middle-aged Caucasian women. The codons 60 to 265 and the codon 294 of the MC1R gene were sequenced in 488 women. The skin color was measured on the inner side of the forearm using a spectrophotometric instrument. Fifteen variants were identified: Arg151Cys, Arg160Trp, Arg142His, Asp294His, Ile155Thr, Asp84Glu, Val60Leu, Val92Met, Arg163Gln, Ser83Pro, Thr95Met, Pro256Ser, Val265Ile, Ala166Ala and Gln233Gln. Women carrying Arg151Cys, Asp294His, Arg160Trp and Asp84Glu variants had a significantly higher reflectance in the red region, which indicates a lower level of functional melanin. This association was the most pronounced for women carrying Asp84Glu. In contrast, no significant difference was observed for other variants. Moreover, associations between MC1R polymorphisms and the risks of experiencing sunburn and of having freckles were found independently of skin color. Our findings support the hypothesis that MC1R polymorphisms do not necessarily alter the skin color but should sensitize the skin to UV-induced DNA damage.     

On the sodium and lithium ion affinities of some α-amino acids

The decomposition of 59 different cluster ions (generated by fast atom bombardment) consisting of two different amino acids and a sodium ion was analysed. The only fragment ions of significant abundance could be assigned to sodium ion-bound amino acids. Assuming that the most abundant ion in the fragment ion spectrum corresponds to the amino acid with the highest sodium ion affinity (SIA), the 20 common α-amino acids could be ordered with increasing sodium ion affinity as follows: Gly, Ala, Cys, Val, (Leu, Ile), Ser, Met, Thr, (Phe, Pro), Asp, Tyr, (Glu, Lys), Trp, Asn, Gln, His, Arg. Quantitative determinations were carried out by comparison of the lithium ion affinity (LIA) of Ala with that of dimethylformamide (DMF) in a fragment ion scan of the ion-bound dimer Ala—Li⁺—DMF. LIA(Ala) was calculated from LIA(Ala) = LIA(DMF) – (1/C)ln[I(AlaLi⁺)/I(DMF—Li⁺)], where the constant C was estimated from measurements of proton-bound amine–amino acid clusters. From fragment ion analysis of nine other Li⁺-bound α-amino acid dimers, the following lithium ion affinities were obtained: Gly 51.0, Ala 52.6, Sar 53.5, α-aminobutyric acid 53.7, glycine methyl ester 54.7 and Val 54.8. SIA(Ala) was estimated to be 75% of the lithium ion affinity and from fragment ion analysis of ten Na⁺-bound α-amino acid dimers the following sodium ion affinities were obtained: Gly 37.9, Ala 39.4, α-aminobutyric acid 40.3, Val 41.0, glycine methylster 41.0 and Sar 41.2.     

Identification of garlic in old gildings by gas chromatography-mass spectrometry

The proteinaceous content of garlic (Allium sativum) was characterised according to its amino acid composition by using a gas chromatography-mass spectrometry (GC-MS) analytical procedure. The procedure was tested on fresh and aged garlic samples as well as on reference gilding specimens prepared according to old recipes. The proteinaceous pattern showed a characteristic distribution of amino acids with glutamic acid being the major component. The average amino acidic composition was: glutamic acid (Glu; 29%), aspartic acid (Asp; 17%), serine (Ser; 11%), alanine, glycine, valine, leucine, lysine and phenylalanine (Ala, Gly, Val, Leu, Lys and Phe; 5-6%), isoleucine, proline and tyrosine (Ile, Pro and Tyr; 2-3%), methionine and hydroxyproline (Met and Hyp; 0.5%). In order to distinguish this material from animal glue and egg, which are the other proteinaceous media commonly used in gilding techniques, a database of amino acid percentages of the three proteins was built up and submitted to principal component analysis. Three separate clusters were obtained, allowing the protein identification. The application of the procedure on several gilding samples from Italian wall and easel paintings (13th-17th century) permitted to evidence the use of garlic as a gluing agent.     

蚕丝丝素纤维中氨基酸在丝素纤维的径向分布研究

通过显微镜观察、红外光谱、氨基酸组成分析、福林试剂分析等方法研究蚕丝丝素纤维的微结构、丝素表层和内层的结构差异 ,研究氨基酸尤其是对丝素纤维的结构和性能起重要影响的主要芳香族氨基酸———酪氨酸在丝素由表及里各层中的含量和分布 ,以期最终揭示丝素结构与蚕丝织物应用中的固有缺陷 (如泛黄、易皱、色牢度等 )的关系 .结果表明蚕丝丝素存在多层次结构 ,表层无定形区的比例较高 ,里层结晶区的比例较高 ;侧基较大的氨基酸和赖氨酸、组氨酸、胱氨酸、精氨酸、天门冬氨酸、苯丙氨酸、亮氨酸、谷氨酸、酪氨酸等在丝素的表层分布相对较多 ,而乙氨酸、丙氨酸、丝氨酸等小侧基氨基酸则在中间层至里层较多     

Effect of side chains on competing pathways for beta-scission reactions of peptide-backbone alkoxyl radicals

High-level quantum chemistry calculations have been carried out to investigate beta-scission reactions of alkoxyl radicals located at the alpha-carbon of a peptide backbone. This type of alkoxyl radical may undergo three possible beta-scission reactions, namely C-C beta-scission of the backbone, C-N beta-scission of the backbone, and C-R beta-scission of the side chain. We find that the rates for the C-C beta-scission reactions are all very fast, with rate constants of the order 10(12) s(-1) that are essentially independent of the side chain. The C-N beta-scission reactions are all slow, with rate constants that range from 10(-0.7) to 10(-4.5) s(-1). The rates of the C-R beta-scission reactions depend on the side chain and range from moderately fast (10(7) s(-1)) to very fast (10(12) s(-1)). The rates of the C-R beta-scission reactions correlate well with the relative stabilities of the resultant side-chain product radicals (*R), as reflected in calculated radical stabilization energies (RSEs). The order of stabilities for the side-chain fragment radicals for the natural amino acids is found to be Ala < Glu < Gln approximately Leu approximately Met approximately Lys approximately Arg < Asp approximately Ile approximately Asn approximately Val < Ser approximately Thr approximately Cys < Phe approximately Tyr approximately His approximately Trp. We predict that for side-chain C-R beta-scission reactions to effectively compete with the backbone C-C beta-scission reactions, the side-chain fragment radicals would generally need an RSE greater than approximately 30 kJ mol(-1). Thus, the residues that may lead to competitive side-chain beta-scission reactions are Ser, Thr, Cys, Phe, Tyr, His, and Trp.     

THE DISTRIBUTION FUNCTION OF RESIDUE-RESIDUE CONTACTS IN PROTEIN MOLECULES

In protein molecules each residue has a different ability to form contacts.In this paper,we calculated the number of contacts per residue and investigated the distribution of residue-residue contacts from 495 globular protein molecules using Contacts of Structural Units(CSU)software.It was found that the probability P(n)of amino acid residues having n pairs of contacts in all contacts fits Gaussian distribution very well.The distribution function of residue-residue contacts can be expressed as:P(n)=P_0+aexp[-b(n-n_c)~2].In our calculation,P_0=-0.06,α=11.4,b=-0.04 and n_c=9.0.According to distribution function,we found that those hydrophobic(H)residues including Leu,Val,Ile,Met,Phe,Tyr,Cys,and Trp residues have large values of the most probable number of contact n_c,and hydrophilic(P)residues including Ala,Gly,Thr, His,Glu,Gln,Asp,Asn,Lys,Ser,Arg,and Pro residues have the small ones.We also compare with Fauchere-Pliska hydrophobicity scale(FPH)and the most probable number of contact n_c for 20 amino acid residues,and find that there exists a linear relationship between Fauchere-Pliska hydrophobicity scale(FPH)and the most probable number of contact n_c, and it is expressed as:n_c=a+b×FPH,here α=8.87,and b=1.15.It is important to further explain protein folding and its stability from residue-residue contacts.     

Essential of Proline and Valine Residues in the Peptide Derived from Lactoferrin for Angiotensin Converting Enzyme Inhibition

We synthesized Leu‐Arg‐Pro‐Val‐Ala‐Ala‐Glu, the peptide contained in lactoferrin (Lf), to identify the angiotensin converting enzyme (ACE) inhibition. In an attempt to know the structure‐activity relationship of this peptide, we replaced Pro (the third amino acid residues from N‐terminal) or Val (the fourth amino acid residues from N‐terminal) with Ala (neutral amino acid), Glu (acidic amino acid) or Lys (basic amino acid) to produce six peptides. From the in vitro ACE inhibition (IC₅₀) of these synthesized peptides, the original peptide (Leu‐Arg‐Pro‐Val‐Ala‐Ala‐Glu) showed higher ACE inhibition than the replaced six peptides. Thus, replacement of Pro at the third amino acid residues or Val at the fourth position with Ala, Glu or Lys revealed the ACE inhibition to be lower than the original form of Leu‐Arg‐Pro‐Val‐Ala‐Ala‐Glu. Otherwise, we added one peptide at the C‐terminal of Leu‐Arg‐Pro‐Val‐Ala‐Ala‐Glu and found both products with an addition of Val (Leu‐Arg‐Pro‐Val‐Ala‐Ala‐Glu‐Val) or Ile (Leu‐Arg‐Pro‐Val‐Ala‐Ala‐Glu‐Ile) showing a lower ACE inhibition than the original one. The ACE inhibitions produced by both replaced peptides were without significance. Also, deletion of the last peptide at the C‐terminal (Leu‐Arg‐Pro‐Val‐Ala‐Ala) failed to produce a marked change of ACE inhibition as compared to the original one. These results suggest that Pro and Val are essential in the peptide for inhibition of ACE activity.     

天花粉蛋白的化学 III:溴化氰降解片段CBa的氨基酸顺序

The results from the study on the separation, purification, amino acid composition and amino acid sequence of CBa, one of the four CNBr degradation fragments of crystalline trichosanthin, are presented. Its amino acid composition is: Asp3, Thr2, Ser2, Hse1, Glu2, Gly2, Ala6, Val1, Tyr3, Phe3, Lys2, Arg1. The sequence of the CBa is Gly-Tyr-Arg-Ala-Gly-Asp-Thr-Ser- Tyr-Phe-Phe-Asn-Glu-Ala-Ser-Ala-Thr-Glu-Ala-Ala-Lys-Tyr-Val- Phe-Lys-Asp-Ala-Hso.     

STATISTICAL PROPERTIES OF LONG-RANGE CONTACTS IN GLOBULAR PROTEINS

The analysis of residue-residue contacts in protein structures can shed some light on our understanding of the folding and stability of proteins. In this paper, we study the statistical properties of long-range and short-range residue-residue contacts of 91 globular proteins using CSU software and analyze the importance of long-range contacts in globular protein structure. There are many short-range and long-range contacts in globular proteins, and it is found that the average number of long-range contacts per residue is 5.63 and the percentage of residue-residue contacts which are involved in long-range ones is 59.4%. In more detail, the distribution of long-range contacts in different residue intervals is investigated and it is found that the residues occurring in the interval range of 4-10 residues apart in the sequence contribute more long-range contacts to the stability of globular protein. The number of long-range contacts per residue, which is a measure of ability toform residue-residue contacts, is also calculated for 20 different amino acid residues. It is shown that hydrophobic residues (including Leu, Val, Ile, Met, Phe, Tyr, Cys and Trp) having a large number of long-range contacts easily form long-range contacts, while the hydrophilic amino acids (including Ala, Gly, Thr, His, Glu, Gln, Asp, Asn, Lys, Ser, Arg, and Pro) form long-range contacts with more difficulty. The relationship between the Fauchere-Pliska hydrophobicity scale (FPH) and the number of short-range and long-range contacts per residue for 20 amino acid residues is also studied. An approximately linear relationship between the Fauchere-Pliska hydrophobicity scale (FPH) and the number of long-range contacts per residue CL is found and can be expressed as     

Investigation of the interactions between ginsenosides and amino acids by mass spectrometry and theoretical chemistry

In order to evaluate the essence of the interactions of ginsenosides and proteins which are composed by α-amino acids, electrospray ionization mass spectrometry was employed to study the noncovalent interactions between ginsenosides (Rb₂, Rb₃, Re, Rg₁ and Rh₁) and 18 kinds of α-amino acids (Asp, Glu, Asn, Phe, Gln, Thr, Ser, Met, Trp, Val, Gly, Ile, Ala, Leu, Pro, His, Lys and Arg). The 1:1 and 2:1 noncovalent complexes of ginsenosides and amino acids were observed in the mass spectra. The dissociation constants for the noncovalent complexes were directly calculated based on peak intensities of ginsenosides and the noncovalent complexes in the mass spectra. Based on the dissociation constants, it can be concluded that the acidic and the basic amino acids, Asp, Glu, Lys and Arg, bound to ginsenosides more strongly than other amino acids. The experimental results were verified by theoretical calculations of parameters of noncovalent interaction between ginsenoside Re and Arg which served as a representative example. Two kinds of binding forms, “head–tail” (“H–T”) and “head–head” (“H–H”), were proposed to explain the interaction between ginsenosides and amino acids. And the interaction in “H–T” form was stronger than that in “H–H” form.     

Sequence composition and environment effects on residue fluctuations in protein structures

Structure fluctuations in proteins affect a broad range of cell phenomena, including stability of proteins and their fragments, allosteric transitions, and energy transfer. This study presents a statistical-thermodynamic analysis of relationship between the sequence composition and the distribution of residue fluctuations in protein-protein complexes. A one-node-per-residue elastic network model accounting for the nonhomogeneous protein mass distribution and the interatomic interactions through the renormalized inter-residue potential is developed. Two factors, a protein mass distribution and a residue environment, were found to determine the scale of residue fluctuations. Surface residues undergo larger fluctuations than core residues in agreement with experimental observations. Ranking residues over the normalized scale of fluctuations yields a distinct classification of amino acids into three groups: (i) highly fluctuating-Gly, Ala, Ser, Pro, and Asp, (ii) moderately fluctuating-Thr, Asn, Gln, Lys, Glu, Arg, Val, and Cys, and (iii) weakly fluctuating-Ile, Leu, Met, Phe, Tyr, Trp, and His. The structural instability in proteins possibly relates to the high content of the highly fluctuating residues and a deficiency of the weakly fluctuating residues in irregular secondary structure elements (loops), chameleon sequences, and disordered proteins. Strong correlation between residue fluctuations and the sequence composition of protein loops supports this hypothesis. Comparing fluctuations of binding site residues (interface residues) with other surface residues shows that, on average, the interface is more rigid than the rest of the protein surface and Gly, Ala, Ser, Cys, Leu, and Trp have a propensity to form more stable docking patches on the interface. The findings have broad implications for understanding mechanisms of protein association and stability of protein structures.     

Cascade Dissociations of Peptide Cation-Radicals. Part 1. Scope and Effects of Amino Acid Residues in Penta-, Nona-, and Decapeptides

Amino acid residue-specific backbone and side-chain dissociations of peptide z ions in MS(3) spectra were elucidated for over 40 pentapeptides with arginine C-terminated sequences of the AAXAR and AAHXR type, nonapeptides of the AAHAAXX"AR and AAHAXAX"AR type, and AAHAAXX"AAR decapeptides. Peptide z(n) ions containing amino acid residues with readily transferrable benzylic or tertiary β-hydrogen atoms (Phe, Tyr, His, Trp, Val) underwent facile backbone cleavages to form dominant z(n-2) or z(n-3) ions. These backbone cleavages are thought to be triggered by a side-chain β-hydrogen atom transfer to the z ion C(α) radical site followed by homolytic dissociation of the adjacent C(α)-CO bond, forming x(n-2) cation-radicals that spontaneously dissociate by loss of HNCO. Amino acid residues that do not have readily transferrable β-hydrogen atoms (Gly, Ala) do not undergo the z(n) → z(n-2) dissociations. The backbone cleavages compete with side-chain dissociations in z ions containing Asp and Asn residues. Side-chain dissociations are thought to be triggered by α-hydrogen atom transfers that activate the C(β)-C(γ) or C(β)-heteroatom bonds for dissociations that dominate the MS(3) spectra of z ions from peptides containing Leu, Cys, Lys, Met, Ser, Arg, Glu, and Gln residues. The Lys, Arg, Gln, and Glu residues also participate in γ-hydrogen atom transfers that trigger other side-chain dissociations.     

Two New Cyclic Tetrapeptides of Streptomyces rutgersensis T009 Isolated from Elaphodus davidianus Excrement

Two new cyclic tetrapeptides, cyclo(l ‐Val‐l ‐Leu‐l ‐Val‐l ‐Ile) ( 1 ) and cyclo(l ‐Leu‐l ‐Leu‐l ‐Ala‐l ‐Ala) ( 2 ), and 15 known compounds, cyclo(Gly‐l ‐Leu‐Gly‐l ‐Leu) ( 3 ), cyclo(l ‐Ser‐l ‐Phe) ( 4 ), cyclo(l ‐Leu‐l ‐Ile) ( 5 ), cyclo(l ‐Tyr‐l ‐Phe) ( 6 ), cyclo(Gly‐l ‐Trp) ( 7 ), cyclo(l ‐Leu‐l ‐Tyr) ( 8 ), cyclo(Gly‐l ‐Phe) ( 9 ), cyclo(l ‐Phe‐trans‐4‐hydroxy‐l ‐Pro) ( 10 ), cyclo(l ‐Leu‐l ‐Leu) ( 11 ), cyclo(l ‐Val‐l ‐Phe) ( 12 ), cyclo(l ‐Val‐l ‐Leu) ( 13 ), cyclo(l ‐Ile‐l ‐Ile) ( 14 ), cyclo(l ‐Tyr‐l ‐Tyr) ( 15 ), turnagainolide A ( 16 ), and bacimethrin ( 17 ) were isolated from the fermentation broth of Streptomyces rutgersensis T009 obtained from Elaphodus davidianus excrement. Their structures were identified on the basis of spectroscopic analysis. Meanwhile, the absolute configurations of the amino acid residues of compounds 1 and 2 were determined by advanced Marfey method. Compound 3 was obtained from a natural source for the first time. The X‐ray single crystal diffraction data of bacimethrin ( 17 ) were also reported for the first time. Compounds 1  –  17 exhibited no antimicrobial activities with the MICs > 100 μg/ml.